2. 04. 2025 Will Steen

Why are rivers important?

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From the creek whispering through a forest, to the confusion of huge currents twisting against each other in the channel. Rivers take on many forms. They are the direct connection between us and the Ocean but why are rivers important?

Read about the wider water cycle and how rivers fit into it here.

Why are rivers amazing? What is an estuary? And what are the threats to these wet wonders?

What are rivers?

Let’s start with a quick definition. Rivers are large, natural flowing streams of water. They have banks on either side, they have a source and a mouth. They meander through every continent, from a few kilometres to thousands long.

Which is the biggest river?

What does ‘biggest’ mean? Let us start with length, and to answer that, let us start with another question: where do rivers start? Finding where a river begins is notoriously difficult.

It’s tricky to work out where that first drop comes from. Some rivers begin from a lake or a melting glacier. Others, like the Danube in Europe, start from a spring (water bubbling out of the ground).

River origin leads to debates over which the longest river is – the Nile or the Amazon.

The Guinness Book of World Records gives the award to the Nile but does concede “which is longer is more a matter of definition than simple measurement”.

The Nile, in Africa, has been estimated as great as 7,088 km (4,404 miles) in length, and the same paper puts the Amazon, in South America, at 6,575km (4,085 miles).

However, a quick search will reveal some debate. 6,650 km (4,132 miles) is more commonly quoted for the Nile, and 6,400 km (3,976 miles) for the Amazon.

Explorers are always trying to prove otherwise, measuring in a different way, from a different point, to a different point.
We are #TeamNile.

Next, there is the deepest river in the world: the river Congo.

It reaches depths of 220m. That is about as deep as the world record for SCUBA diving. By that depth there is little light, and the pressure from the water above is equivalent to having three adult orcas lying on top of you.

The Amazon stands alone in the amount of water it gathers.

Once rivers start their journey, they gather in momentum on their mission back to the Ocean. More precipitation and groundwater help fuel their flow, and other streams, known as tributaries, join it along the way.

Approximately 209,000m^3/s of water enters the Atlantic from the Amazon. This is equivalent to almost 20% of the total global river discharge, the total volume of water rivers release into the Ocean.

The Amazon is more than the Nile, the Mississippi, in the USA, and the Chang Jiang (Yangtze), in Asia, combined. The brown waters can be seen as far as 100km (62 miles) out to sea, which provided an important navigation tool for sailors hundreds of years ago.

The biggest rivers on Earth, posted by Ocean Generation.

Where are estuaries?

Where the river reaches the Ocean, the interface is an estuary. They usually have a mix of fresh and salty water, known as brackish (there are some examples of freshwater estuaries in the Great Lakes of North America).

Estuaries are highly productive, unique ecosystems. For many different animals they provide food, places to breed, nursery grounds and hosting migratory species.

But why do rivers matter?

Rivers are important, as fresh water is key to all life. Rivers have influenced our world historically, geologically and culturally. They support life where it would otherwise be unviable, on land and in the Ocean. They are the ultimate connector.

Approximately 40 trillion cubic metres of water enters the Ocean from rivers every year. But it doesn’t come alone.

As water moves over the land, it picks up hitchhikers (such as ions, making the sea salty – see more here). Material dissolves into the river, or the water pulls it along. These can lend colour to the river waters (and often their names).

There is the Rio Negro in Brazil, named due to the humic acid from decomposing vegetation colouring the water black. The Red Rivers in Peru and North America, from the small pieces of rock containing iron oxides. The Drina in central Europe is green due to the limestone it flows over and the Hwang Ho (Yellow River) in China is named so because of the loess (a type of soil or sediment) it carries.

They do more than just look good; these multicoloured masses are changing the world.

Freshwater is key to all life on Earth. Posted by Ocean Generation.

How do rivers change the world?

Flowing over rocks, mud and sand, each particle that the waters pick up change the course of the river and the shape of the land. Look around where you live, you can usually find the fingerprints of water at work.

Rivers can cut away land and form new land, depositing the sediment it has picked up on the bank or in deltas where they meet the Ocean.

The Colorado River, in North America, has produced the most remarkable example, carving away the landscape to produce the Grand Canyon, while the Nile Delta shows us how rivers build land too.

The waters are full of nutrients, iron, nitrates and other essential building blocks for life. When these enter the Ocean, life flourishes.

How are rivers and estuaries important for us?

Rivers are incredibly important for one species in particular: us.

The first great civilisations all rose up on rivers. The Nile, the Indus, the Tigris and Euphrates and the Huang all supported some of the earliest great cities in human history. Think of a big city – if it isn’t on the coast, we bet it is on a river.

Rivers provide food: the last two very long uninterrupted rivers in Southeast Asia, the Irrawaddy and Salween, provide 1.2 million tonnes of catch annually and support agriculture of over 30 million people. In the US, approximately 68% of the commercial fish caught were caught in estuaries.

The water rivers carry is crucial for drinking, domestic use and agriculture. More recently, we use it for power and industry, and transport.

Rivers have held a central place in culture as well, connecting us and our world metaphysically.

The Whanganui river in New Zealand has been regarded as an ancestor by the Māori people for centuries, and the Ganges is upheld as a place of healing and purity, personified by the goddess Ganga. In Japan, Shinto beliefs hold that each river has its own divine guardian, the Kawa-no-Kami.

Across many different cultures, rivers have been celebrated and protected.

Why do rivers matter? Posted by Ocean Generation, leaders in Ocean education.

What are the threats to the rivers?

As much as rivers have impacted human civilisation, we have had our impact on them.

Changes to our water cycle due to climate change have reduced the resilience of our rivers as they experience larger variations in flow. Add that to pollution, developing on their banks, extracting their flora and fauna and even stopping their flow – rivers have had it tough.

In order to harness the power of our rivers, we have been interrupting their flow. Just 23% of rivers over 1000km long flow uninterrupted into the Ocean, broken up by an estimated 2.8 million dams.

How does pollution affect rivers?

It is important to realise there are lots of different types of pollution. The first and most obvious is big pollution – plastic, waste, shopping trolleys – that kind of thing. This rubbish can damage the life in the river itself, spoil the water for use and clog and disrupt the water flow.

The other kind of pollution is the small stuff – chemicals, microplastics and pharmaceuticals. These can disrupt aquatic wildlife, make the water unsafe to drink and accumulate through the food chain.

The Ganges, in India, is now a stark example of river pollution. In Hinduism, the river is personified as the goddess Ganga, the goddess of purity.

Just 37% of sewage is treated before entering the river. The banks are lined with tanneries, slaughterhouses, textile mills, chemical plants and hospitals. The waste that fills the river has an estimated 66% occurrence of waterborne disease and contains super-bacteria resistant to antibiotics.

How are estuaries under threat?

Estuaries face many of the same threats as rivers. An estimated 55% of global wetland areas has been lost since 1900, due to developing coastal areas. These wetlands provide unique habitats for their inhabitants, who often are not suited to either the freshwater or marine environments.

We also benefit from the carbon dioxide absorption, offsetting our emissions, and the reduction in the risks of flooding and coastal erosion.

But we are poisoning them too. Chemicals – pesticides and fertilisers – used in agriculture, are washed into rivers and accumulate in estuaries. This leads to nutrient overloading, or eutrophication, with harmful algal blooms appearing. When these die, the decomposition uses up the oxygen in the water – impacting the animals living there.

Estuaries absorb carbon dioxide. Posted by Ocean Generation

How can we look after our rivers?

Everything is connected, which means you can make a difference from anywhere. Simply being aware of the connection you have with the Ocean is an important step. You can look after it, wherever you are.

Rivers connect us directly to the Ocean. A hot take? All life is essentially marine – everything is connected to and dependent on the Ocean.

Along with estuaries, they provide important habitats, give us the water we need to survive and bring us closer together through transport and culture. But they are threatened in our new world. As ever, being aware is such a crucial first step to solving any issue.

Educate others:

Share information about river conservation and encourage others to take action.
Engage in local initiatives that promote sustainable water management practices.

Join community and advocacy events:

Participate in local river clean-up events to help maintain waterways and raise awareness

Advocate for sustainable practices:

Support policies that protect rivers from pollution and over-abstraction
Promote low-impact renewable energy to preserve free-flowing rivers
Be aware of what you use. Harsh chemicals for cleaning and gardening will eventually enter our Ocean. Check your shampoo for harmful chemicals and microplastics.

Next time you are by a river, take a moment. That is a direct line to the Ocean. See if you can understand the connection humans have felt with rivers throughout our history. Wonder at the power and beauty. Appreciate the importance of our rivers.

You can make a difference from anywhere.

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Will Steen

Why are rivers important?

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8. 12. 2024 Will Steen

COP29 outcomes: Wins and disappointments

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COP29 finished on the 24th November 2024, after two weeks of tough, technical negotiations.

It was full of colouring books, expensive sandwiches and drama! Let’s break down the COP29 outcomes: the wins and disappointments – and have a look across to COP16 (the biodiversity one) too.

What is COP16? Why are there multiple? What are all the acronyms? Read our explainer here.

Money, money, money.

COP29 was held in Baku, Azerbaijan and was painted as the ‘finance COP’ with the hopes of a climate finance deal being agreed.

Hold up – what is climate finance? Broadly speaking, climate finance refers to any money “that seeks to support mitigation or adaption actions that will address climate change” – UNFCCC (remember what it stands for? Spoiler: United Nations Framework Convention on Climate Change)

Richer countries – often referred to as the Global North (that also includes Australia, Israel and New Zealand) – have emitted the vast majority of the CO2 that is responsible for climate change. As of 2019, the Global North have emitted 2.5 times their fair share of the emissions allowed for 1.5 degrees of warming.

Countries in the Global North industrialised much earlier than the Global South, making a lot of money at the cost of carbon dioxide emissions. It has been called for, and agreed, that the richer countries should provide money to the developing countries, to allow them to develop without emitting so much CO2.

Furthermore, there’s a loss and damage fund to help countries most affected by climate change. Many of the countries most vulnerable to the effects of climate change (sea level rise, droughts, heatwaves, floods, intense storms etc.) are poorer countries.

What were the themes of COP29?

So, what actually happened this year? Let’s explore a few of the themes that came from the COP29 summit this year.

Presents and petrol stations.

Countries have their own stands – as an opportunity for cultural sharing and integration. Many gave out gifts: Georgia handed out some wine tasters, the UK provided coffee.

Go to the Russian stand and you could pick up an ecological colouring book, full of tips for environmental sustainability. Some were slightly cynical, as it was produced by a major fossil fuel company.

What were the themes of COP29? Explained by Ocean Generation. — *Photos by Dharna Noor/ The Guardian*

Fossil fuels have been present throughout COP29. Azerbaijan, the host country, is a country with 90% of its exports comprised of fossil fuels. The capital, Baku (save that for the pub quiz) houses the very first industrial oil well and was the world’s first oil town (dating back to the 1840s).

For the second year running, COP was attended by more fossil fuel lobbyists than the ten most climate change vulnerable countries‘ delegations combined. The host nation Azerbaijan, next year’s host Brazil and one of the countries competing for COP31 presidency, Turkey, were the only countries with more attending.

Although the 1,773 attendees from fossil fuel companies made up only 1.5% – there were only three countries with more.

Should discussions around climate change happen in the house of the industry most responsible for the damage?

Or does it represent an opportunity to engage and include those most capable of changing our world?

Al Gore said, “It’s unfortunate that the fossil fuel industry and the petrostates have seized control of the COP process to an unhealthy degree.”

Or, as Oil Change International member David Tong said: “It’s like tobacco lobbyists at a conference on lung cancer.”

The president of Azerbaijan made headlines this year describing oil and gas as “a gift from God”. This was denounced by a multitude of faith groups. And the Brazilian environment minister Marina Silva said: “We should take care in moderation of the gifts we are given – if we eat too much sugar, we get diabetes.”

A report published during COP highlighted that eight fossil fuel companies had paid at least $17.6 million to Meta (which owns Facebook and Instagram) alone for pushing their posts – 700 million impressions, all within the last year.

Al Gore quote about fossil fuel lobbyists at COP29. Posted by Ocean Generation.

Activism has always been a big part of COP.

It presents an opportunity to make voices heard by the decisionmakers and gives a platform to send big messages.

Attendees of the COP29 summit were welcomed by a realistic, full-sized model of a dead sperm whale on the waterside in Baku. Created by Belgian art collective Captain Boomer, the piece hopes to highlight “the disruption of our ecological system”.

In the run-up to COP29, the cop29.com website was acquired by Global Witness, which called for fossil fuel CEOs to pay for the damage they have done to the climate.

There was a protest outside BP headquarters in London, and a number of demonstrations in Baku, including a large snake, with the message “weed out the snakes” – aimed at the fossil fuel attendees.

Activism at COP29 presents an opportunity to make our voices heard.

COP29: Agreements and outcomes.

After two weeks, and running over by 34 hours, COP29 closed with a number of agreements. What did all the sleepless nights in smelly conference halls produce? (at one point the plumbing failed, filling the corridors with the smell of you-know-what).

There were finally some numbers for climate finance – $1.3 trillion per year, needed by 2035. This number is based in the recommendations of the Independent Expert Group on Climate Finance (IHLEG). “At least” $300 billion of this is to come from developed countries. The rest could come from a range of sources including private finance and taxes on cryptocurrency, airplane tickets and the super-rich – known as solidarity levies.

There was no agreement reached on how to take the Global Stocktake from COP28 forward, so it was pushed back to COP30 next year.

Article 6 of the Paris Agreement, describing ‘carbon markets’, was finalised, marking the last element of the Paris Agreement to be completed, although it was not agreed on. This just means that the text has been written, but countries have not yet signed on the dotted line.

The reaction to COP29 has been, optimistically, mixed.

The focus, following on from the expectations coming into COP29 (finance COP), has been on climate finance. The amount pledged by the Global North has come under fire: “A paltry sum” and “a joke” by delegates from India and Nigeria respectively.

However, some took a more positive view. Marshall Islands climate envoy Tina Stege said, “it isn’t nearly enough, but it is a start”. An observer was quoted by the Carbon Brief as saying, “momentum was neither lost nor gained, just maintained” so overall, it achieves “a passing grade”.

UNFCCC (remember what that stands for?) Executive Secretary Simon Steill said:

“This new finance goal is an insurance policy for humanity, amid worsening climate impacts hitting every country. But like any insurance policy – it only works – if premiums are paid in full, and on time. Promises must be kept, to protect billions of lives.”

$300 billion per year, it has been widely agreed, is not enough. But the creation of a deal is a good step and could be enough to spur on the further investment required from private finance and new sources, such as carbon markets and new taxes.

What happened at COP29 and COP16: Explained by Ocean Generation.

Outside the negotiating rooms.

Beyond the walls of formal negotiations, there were some big developments.

Indonesia, the 8^th biggest emitter of CO2, unexpectedly pledged a complete phase out.
Mexico was the last G20 country to not commit to net zero, but did during COP29.
UK and the EU joined 30 nations in an agreement to slash emissions further, specifically targeting methane emissions.
China’s influence grew in the absence of strong US leadership. It announced the opening of the largest wind farm in the world.
Some NDCs (Nationally Determined Contributions) announced: UK pledged a reduction of 81% against 1990 levels by 2035. Brazil announced a 59-67% reduction against 2005 levels.
At COP29, over 70 events were hosted in the dedicated Ocean Pavilion over the two weeks.

What happened at COP16 (the biodiversity summit)?

Just 10 days before the first delegates landed in Baku, COP16 wrapped up in Cali, Columbia. This followed very similar themes. It was focused on money. Specifically, where to find the money required to tackle biodiversity loss and restoration.

The Cali Fund was established and though limited in being entirely voluntary with debated scope, can be a positive step.

Another main objective for COP16 was the updating National Biodiversity Strategies and Action Plans, and unfortunately only 44 countries out of 196 had done so by the end of the conference.

119 countries submitted national biodiversity targets, building on the work of the Global Biodiversity Framework agreed on at COP15.

COP16 formally recognised the importance of indigenous peoples and local communities (IPLCs) to conservation efforts, creating a body to amplify their voices in the CBD.

At COP16, the Ocean was prominent in a way not previously seen.

The Small Island Developing States (SIDS) pushed for progress. The Maldives announced14% protection of their coral reefs with more protection pencilled in. The Azores announced the largest MPA network in the North Atlantic, protecting 30% of its waters.

Parties approved a new process to identify ecologically or biologically significant marine areas (EBSAs) (bet you thought we were done with new acronyms).

This doesn’t guarantee protection but can guide the creation of marine protected areas (MPAs) in areas that will be most effective, including the high seas.

Generally, the progress made for the Ocean was received very positively.

COP29 and COP16: the transition from negotiation to actions.

Awareness, knowledge and respect for the natural world is growing. Frustration at pace of progress is evident throughout the process, from those in the room to those hearing the news. We need to appreciate how far we have come, while also maintaining the push onwards.

What was top of the COPs?

Tops	Nots
Agreement to triple climate finance to $300 billion	Amount falls far short of that hoped by developing countries
Carbon markets approved after a decade of trying	Fears of carbon markets being misused in bad offsetting and fraud
Cali Fund established	No mandatory contributions – entirely voluntary, no guarantees
Loss and Damage Fund should be operational in 2025, and has $730 million pledged	No further progress on last year’s Global Stocktake – phasing out fossil fuels
Mexico and Indonesia surprise with net zero and emission cutting announcements	Some countries and parties obstructing progress
China announces more voluntary contributions to climate finance

COP29 ment a transition from negotiations to actions. Posted by Ocean Generation.

Brazil has made it clear it intends to make COP30 a “Nature COP”. If it can maintain momentum, COP29 has given foundation for the transition into tangible action.

These big global treaties can feel very far away, and it can seem that there is nothing you or I could do. But we are the key parts of this puzzle. Appreciate every small action you take.

Turn down your heating by one degree this winter – barely enough to notice but saving a lot of emissions.

Be conscious of what you eat – choosing local, seasonal food can be your difference.

Get talking. You are already doing something important – staying informed. Having conversations with other people, making people more aware, is a crucial part of the process. Engage with us! We love to hear the actions you are taking, and we will answer every question sent our way.

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Will Steen

Why are rivers important?

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8. 12. 2024 Will Steen

Everything you need to know about COP: COP29, COP16s and the things between

Everything you need to know about COP: Explained by Ocean Generation.

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Heard a lot about the COP conferences but not sure what’s going on? Acronyms got you all in a twist?

Welcome to a white-knuckle ride into climate-summit world, where we explain everything you need to know about COP.

What is COP?

COP is our first acronym (can be written as Cop or all in caps). It stands for Conference Of the Parties, the name given to the group of countries (Parties) all coming together to make big decisions.

It consists of negotiations between representatives, presided over by the host country. They’re also used as a platform for scientific developments and activism: talks are held, and papers are released aiming to maximise impact.

Why are there multiple COPs?

COP is most used to refer to the COP of the United Nations Framework Convention on Climate Change (UNFCCC) – the big annual summit on climate change. The 2024 edition was the 29^th summit, so it is known as COP29 – easy!

But COP can be used to describe the meetings held for other conventions too.

2024 also had the COP for the United Nations Convention on Biological Diversity (UNCBD) in October and the COP for the UN Convention to Combat Desertification (UNCCD) in December. Both of these are biennial (one every two years) and meeting for the 16^th time, so both are known as COP16 – useful (not).

Three conventions of the Rio Trio aim to tackle threats to humanity. Posted by Ocean Generation

The three COPs were all created at the UN Earth summit in 1992 in Rio de Janeiro, so are known as the ‘Rio Conventions’ or more informally the Rio Trio. They aim to tackle three major threats to humanity – climate change, biodiversity loss and desertification.

The most famous COP outcome was the Paris Agreement.

The Paris Agreement was negotiated at COP21 in 2015. You’ll never guess where. It’s a legally binding (means enforceable by law) agreement with the primary goal of keeping global average temperature well below 2 degrees above pre-industrial levels.

The basic plan? Every country gradually ramps up their climate actions, detailed in Nationally Determined Contributions (NDCs). NDCs are refreshed every five years, and the next round are coming in 2025 – watch this space.

The Agreement also provides a framework of support between countries. Financial, technological and capacity building support is guide lined to enable and encourage cooperation.

Countries also established an enhanced transparency framework (ETF) for gathering relevant data, which will then feed into the Global Stocktake, the progress report for our climate. The Global Stocktake will be published every five years, with the first released last year at COP28.

Everything you need to know about COP: The Ocean is our biggest ally against climate change.

What does COP mean for the Ocean?

This depends which COP you are talking about.

Climate change is a global threat, against which the Ocean has acted as our shield for years. The Ocean absorbs excess heat and carbon dioxide, maintaining our biosphere’s balance. Ocean acidification, marine heat waves and intensifying weather patterns are just some symptoms of a stressed system.

The Ocean is our biggest ally against climate change and the actions at COPs can safeguard our Ocean. While they are not specific to the Ocean, the decisions made at COP can decide the health of our Ocean ecosystems.

The CBD COP (the biodiversity one) is more directly linked to the Ocean: at COP15 the Kunming-Montreal Global Biodiversity Framework officially set the target to protect 30% of countries land and seas by 2030, known as the 30×30 agreement.

Read more about the agreements made at COP29 and learn more about the outcomes of COP16 here.

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16. 10. 2024 Thi Nguyen

How Climate Change threatens polar species: Polar bears, Orcas and Narwhals

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Many polar species depend on sea ice for essential activities like resting, hunting, and avoiding predators but climate change poses a threat.

Polar species have finely tuned their behaviours, and physiological traits to the seasonal advance and retreat of sea ice.

However, as sea temperatures rise and the Arctic (in the Northern Hemisphere) warms at four times the global average rate, sea ice is shrinking and breaking up earlier each year.

This trend presents growing challenges for polar species that rely on ice, highlighting just how important it is to tackle climate change to ensure their survival.

How polar bears are impacted by climate change

Characterised by their large size, dense white fur, and flattened cranium, polar bears are apex predators in the Arctic ecosystem. Their primary prey are ice-dependent seals, particularly ringed and bearded seals.

Seals use the ice as a platform for resting, breeding, and giving birth. Using an ambush technique, polar bears wait at seal breathing holes, catching seals as they come up for air. This saves them energy compared to more active hunting methods.

Ringed and bearded seals in the Arctic, posted by Ocean Generation

Polar bears’ hunting success peaks in the spring and early summer, coinciding with the weaning period of seal pups. This makes it a critical time for the bears to build fat reserves essential for survival through winter.

Climate change delays sea ice formation in autumn, and it’s reducing the time available for hunting seals later in the year. As a result, it’s becoming increasingly difficult for polar bears to build or maintain their fat reserves.

Increased fragmentation of sea ice also forces polar bears to swim longer distances to reach stable ice. In some regions, polar bears have been recorded swimming over 50km. This is an energy draining task for these not-so efficient swimmers, due to their paddling motion and the added drag of swimming at the water’s surface.

Polar bears wait at seal breathing holes

With summer sea ice disappearing, polar bears are becoming more dependent on food sources on land. These offer far less nutrition compared to the energy-rich blubber of seals and increases human-wildlife conflict.

They are currently listed as Vulnerable under the IUCN Red List (last assessed in 2015), facing threats from residential and commercial development, human disturbance and climate change.

How narwhals are impacted by climate change

Narwhals, distinguished by their long, protruding tusks, are remarkable divers capable of reaching depths of up to 1,500 meters in pursuit of prey. Their diet primarily consists of fish (Greenland halibut in particular), cephalopods (such as squid), and crustaceans.

Narwhals depend on breathing holes in the ice to survive

To support their slow, endurance swimming, narwhals have evolved a high proportion of specialised slow-twitch muscles, which make up about 90% of the muscle fibre in their bodies. These muscles are rich in myoglobin. This is an oxygen-binding protein that enhances their ability to store and use oxygen efficiently during extended dives.

Narwhals, like other marine mammals, depend on the stability of breathing holes in the ice to survive. However, climate change has made these ice conditions increasingly unpredictable, leading to entrapment and fatalities for narwhals when they can’t locate a breathing hole.

Their narrow temperature range coupled with strong attachment to specific locations and migratory routes makes them particularly vulnerable in the rapidly warming Arctic.

Currently listed as Vulnerable on the IUCN Red List (last assessed in 2023), narwhals are increasingly threatened by climate change, as well as energy production and mining activities.

How orcas are impacted by climate change

Orcas inhabit the Oceans worldwide, ranging from polar regions to tropical waters. They are categorised into three distinct forms, A, B and C, with type B exhibiting cooperative hunting behaviour in pursuit of seals. In these strategies, family group members work together to create synchronised waves that wash seals off the ice.

Orcas find new opportunities in the changing polar regions

When searching for potential prey, orcas adapt their travel behaviours to the surrounding ice conditions. In open water with minimal ice, they tend to stay close together, while in pack ice, they spread out and often travel as individuals or pairs.

Near ice floes (thin sheets of frozen seawater), individuals engage in spy-hopping to locate seals, taking multiple views from various angles around the edge of the floe.

After observing, they swim away briefly to vocalise and communicate with other group members before returning.

Before attacking, the whales swim together in loose formation, often rolling at the surface. They move side-by-side away from the ice floe before charging back rapidly in a coordinated manner, generating waves as they approach.

Depending on the size of the floe, they create two distinct wave types. One is a breaking wave for smaller floes that can wash seals directly into the water, the other is a non-breaking wave for larger floes that shatters the ice and drives seals off.

Many Arctic marine species use frozen areas as a refuge from orcas.

Bowhead whales, which can break through the sea ice to create breathing holes, face few predators besides humans and orcas. However, as sea ice shrinks, orcas are increasingly detected in Arctic waters.

Many polar species use frozen areas as a refuge from orcas, but climate change and shrinking sea ice threatens them. Posted by Ocean Generation

While this provides new prey opportunities for these apex predators, it could significantly stress prey species, potentially altering their behaviour and population sizes. For example, the specialised locomotor muscles of narwhals make them too slow to escape orcas.

Moreover, the increased presence of orcas may impact indigenous communities that rely on subsistence hunting to sustain their way of life.

Orcas are currently listed as Data Deficient under the IUCN Red List (last assessed in 2017). This highlights the need for more research to comprehensively understand population trends and conservation priorities.

Turning climate challenges into opportunities

The survival of polar species is increasingly threatened by climate change, which leads to shrinking sea ice and altered ecosystems.

These changes not only challenge the feeding and breeding behaviours of these animals but also affect indigenous communities that depend on these species for their livelihoods.

We can help through supporting conservation organisations, taking climate action, advocating for policy change, engaging in sustainable practices, and raising awareness about our impacts on polar ecosystems.

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Thi Nguyen

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14. 10. 2024 Thi Nguyen

Surviving the Polar Regions: Animal strategies and adaptations

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The polar regions are among Earth’s most unique environments

Characterised by low temperatures, limited food availability, harsh climates and extreme seasonality, it’s challenging to live in the polar regions. Species inhabiting the Arctic and Antarctic have evolved various physiological, morphological (structural), and behavioural adaptations to survive in these challenging conditions.

Where is the Arctic? Where is the Antarctic?

The Arctic is in the Northern hemisphere whereas Antarctica is in the Southern hemisphere.

Iconic Arctic species include the polar bear, Arctic fox, narwhal, walrus, and bearded seal.

In contrast, the Antarctic is home to species such as the leopard seal, Emperor and Adélie penguins, and rock ptarmigan (a medium-sized game bird).

Iconic Arctic and Antarctic animals, posted by Ocean Generation.

Slow and steady is key to survival.

Temperature has a major impact on how fast species develop. A pattern of slow development rates has been observed among Antarctic marine ectotherms (species that rely on the environment to regulate their body temperature).

For example, the development rates of marine larvae are slower at low temperatures compared to those in temperate and tropical regions. This is likely due to lower temperatures reducing protein synthesis and folding, resulting in fewer functional proteins available for growth.

With the close link between metabolism and development, polar species tend to have slower metabolic rates and use up minimal energy. Antarctic Nototheniodei fish, for instance, have evolved with reduced quantities of red blood cells and haemoglobin , the protein responsible for transporting oxygen throughout the body.

This reduction in haemoglobin reflects their lower metabolic rates and oxygen demands compared to species in warmer, temperate climates. Slow metabolism and development are key to surviving with the limited food available in the polar regions.

Slow metabolism and development are key to surviving in the polar regions.

How species cope with food scarcity in the polar regions

The polar regions experience dramatic seasonal shifts in solar radiation, with continuous daylight in the summer and nearly total darkness in the winter.

This is accompanied by blizzards, freezing temperatures and limited food availability.

During winter, reduced sunlight limits the growth of primary producers like phytoplankton and plants, which in turn affects the entire food chain. Additionally, the sea ice that forms over the Ocean restricts access to open water, where many marine animals feed. Snow cover makes it more challenging for land animals to access their food sources.

For some animals, these harsh winter conditions are too extreme, and they migrate to more favourable areas. For those that remain, many build up fat reserves during the summer and early autumn to prepare for the limited food availability.

How animals cope with food scarcity in the polar regions

In the Svalbard rock ptarmigan, for example, these fat reserves are primarily used during episodes of acute starvation rather than supplementing daily energy needs.

Some animals also exhibit surplus killing and hoarding behaviour in the summer, such as the Arctic fox. The fox has been observed storing food, with one cache containing as many as 136 seabirds.

Many animals will limit physical activity to conserve their energy and reduce their resting metabolic rate. This refers to the amount of energy the body uses at rest to maintain basic physiological functions.

Adult King penguins can go without food for up to one month. Meanwhile, chicks can endure fasting for up to five months during the subantarctic winter, losing up to 70% of their body mass while relying mostly on stored fat reserves.

Small invertebrates that live on the seafloor, or meiofauna, have adapted to polar environments by feeding on degraded organic matter, which remains available year-round.

In many Arctic marine mammals, the milk produced for their young is exceptionally rich in energy and nutrients, which is vital for the pups to survive in the harsh, cold environment.

How animals cope with freezing temperatures, explained by Ocean Generation, leaders in Ocean education

How species cope with freezing temperatures

Air temperatures in the polar regions can occasionally drop to -60°C, while Ocean temperatures are close to freezing. To maintain a stable core temperature, organisms must employ strategies to minimise heat loss through conduction, convection, radiation, and evaporation.

One common adaptation is the evolution of a rounded body shape to reduce exposed surface area. For instance, walruses have a large, tubular body with minimal projecting extremities, such as visible ears or a tail, reducing heat loss through conduction and convection.

Rounded body shapes help cope with freezing temperatures of the polar regions.

Many polar species develop dense fur for insulation, such as reindeer and caribou (also a species of deer), whose hollow guard hairs provide air-filled cavities for additional warmth. In marine animals, where fur offers little insulation value, a thick layer of blubber becomes essential for protection against cold seas. It also serves as a food reserve.

Many species have evolved sophisticated blood flow regulation systems in body parts exposed to the cold. In marine mammals, a network of blood vessels in the flippers operates as a counter-current heat exchange system. This is when warm blood flows to the flipper transferring heat to cooler blood returning from it. This adaptation allows them to conserve heat in critical areas while maintaining functionality in their extremities.

Moreover, both Arctic and Antarctic fish have independently evolved antifreeze glycoproteins, which are secreted into their blood to prevent the formation of harmful ice crystals. These compounds are produced during the cold winter months in Arctic fish and year-round in Antarctic fish.

Behavioural adaptations also play a key role in survival

Emperor penguins form large huddles in extreme Antarctic cold and wind, with groups consisting of hundreds of individuals. The penguins take turns occupying the warmer centre of the huddle, where ambient temperatures can reach 37.5°C, helping conserve energy and incubate eggs during the winter.

Emperor penguins form huddles to shelter from the cold

Snow place like home

Survival in the polar regions requires a combination of physiological, morphological and behavioural adaptations, enabling species to endure extreme cold, limited food availability and harsh climatic conditions.

As climate change continues to alter these environments, the ability of polar species to adapt will be crucial for their ongoing survival in an increasingly warming world.

Check out How Climate Change threatens polar species: Polar bears, Orcas and Narwhals, where we discuss the opportunities and challenges for animals in a changing world.

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11. 10. 2024 Thi Nguyen

Balancing conservation and community in polar wildlife conflicts

Balancing community and conservation in polar wildlife conflicts

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Addressing human-wildlife conflict is essential for both wildlife conservation and human well-being.

As human populations expand into natural habitats, finding solutions that promote coexistence between people and wildlife becomes increasingly important. By fostering harmony, we can support thriving species, healthy ecosystems, and positive relationships between local communities and conservation efforts.

Reducing conflicts benefits wildlife and eases financial losses for local communities. It also aligns with the UN’s Sustainable Development Goals by enhancing livelihoods, building community resilience, and creating economic opportunities for local populations.

Mitigating human-wildlife conflict on land

Climate change intensifies human-wildlife conflict by changing the historical range and behaviour of wild species, increasing the frequency of interactions between humans and wildlife.

Climate change intensifies human-wildlife conflict. Posted by Ocean Generation, leaders in Ocean education.

While addressing climate change is key to reducing these conflicts, communities can adopt strategies to minimise interactions with conflicting species. Some of these approaches are listed below:

Fencing key resources, such as livestock, and securing protected areas. Planting buffer crops could also reduce wildlife consuming important resources.
Implementing animal-safe food storage facilities and improving waste management systems can prevent wildlife from being attracted to human food sources.
Integrating guarding measures, such as specialised livestock-guarding dogs or patrol officers, into resource protection could provide early warning signs to alert residents to potential conflicting wildlife.
The use of non-lethal deterrents, such as visual, chemical, and acoustic repellents, can further discourage wildlife from approaching human settlements and resources.
Economic costs of conflicts could also be reduced through compensation schemes, alternative income generation, or increasing wildlife-related tourism.

A better understanding of animal movement can help predict high-risk areas and times, allowing for more targeted mitigation efforts. For example, researchers studying moose found that the risk of vehicle collisions increases in winter when snow depth is below 120 cm and nighttime traffic is higher due to longer nights.

This highlights the need for seasonally adaptive strategies to mitigate such risks.

Mitigating human-wildlife conflict in the Ocean

Fishers have several options to minimise encounters with marine mammals.

Ocean mammals often become entangled in fishing lines

Mammals often collide with or become entangled in vertical lines attached to buoys, which mark where nets have been set. To prevent wildlife harm and gear damage, fishers could reduce the number of vertical lines in the water column or use ropes in colours more visible to mammals.

Common rope colors like yellow, green, or blue may be difficult for whales to detect. Switching to colours such as white, black, or striped patterns could make the ropes more visible to whales, potentially helping them avoid entanglement.

Another approach involves weakening lines so that entangled animals can break free more easily. However, this solution can result in financial losses due to reduced catch and replacing lost gear.

Technological innovations, such as acoustic buoy releases that surface only when triggered, could eliminate the need for vertical lines. Another potential solution is the use of pingers, which are devices placed on lines that emit noises at specific frequencies to warn whales and other marine mammals away from boats and fishing gear.

Fisheries-have-several-options-to-minimise-encounters-with-marine-animals

While these strategies could help reduce human-wildlife conflict in fisheries, more testing is needed to see how effective they are. Supportive initiatives, like financial compensation programs to cover losses from wildlife, can ease the economic strain on fishers and encourage the use of non-lethal deterrents.

Collaboration between scientists and communities is key to solving these challenges. For example, the Alaska Longline Fishermen’s Association partnered with biologists and bioacoustic experts in 2003 to study whale behaviour and minimise interactions with longline boats. This led to the creation of the Southeast Alaska Whale Avoidance Project (SEASWAP), a successful project improving our understanding of depredation.

Balancing conservation and community needs

The key to addressing human-wildlife conflict involves recognising and valuing the diverse attitudes towards conservation that influence both the conflict and resolution.

By appreciating the different perspectives of stakeholders, conservation plans can be designed to address the needs and interests of everyone involved. Engaging meaningfully with communities is key to developing policies that are not only effective but also widely supported.

Balancing conservation and community to mitigate polar wildlife conflicts, posted by Ocean generation

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9. 10. 2024 Thi Nguyen

Bearly coexisting: Human-wildlife conflict in the polar regions

Human-wildlife conflict in the polar regions: Explained by Ocean Generation

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As human populations grow, we’re getting closer to natural habitats, leading to increased interactions with wildlife.

Conflict arises when wildlife presence poses real or perceived costs to human interests or needs, like loss of livestock, crop raiding or attacks on humans.

Human-wildlife conflict can have negative impacts on wildlife and can also affect community dynamics, commodity production, and sustainable development.

Conservation biologists are increasingly concerned about human-wildlife conflict in the polar regions – the Arctic in the Northern Hemisphere and Antarctic in the Southern Hemisphere.

Why is human-wildlife conflict increasing in the polar regions?

The polar regions are characterised by low temperatures, extreme seasonality, and the seasonal advance and retreat of sea ice. Both polar regions are home to numerous endemic species, but their survival is threatened by climate change, fishing, tourism, invasive species, and pollution.

Experts are concerned about human-wildlife conflict in the polar regions. Posted by Ocean Generation.

These pressures often lead to more frequent encounters between people and wildlife, especially in the Arctic where around 4 million people live.

A recent study on protecting Antarctic biodiversity found that current conservation efforts are insufficient. It’s predicted that around 65% of land animals and land-associated seabirds could decline by 2100 if global greenhouse gas emissions continue on their >2°C trajectory. The study suggests several ways to boost conservation efforts, such as:

Improving the quality of land that has been polluted or negatively impacted by human use
Managing infrastructure
Protecting areas
Controlling non-native species and diseases

How does human-wildlife conflict appear in the polar regions?

Encounters between people and polar bears

Polar bears are an iconic Arctic species, distributed across 19 subpopulations within five countries: the United States, Canada, Greenland, Norway, and Russia. They rely on sea ice for hunting (primarily seals), breeding, and resting.

With climate change accelerating and sea ice diminishing, polar bears are forced to spend more time on land. Here finding natural food sources becomes challenging, so they often seek out human settlements for a predictable source of nutrition.

The town of Churchill, Manitoba, Canada, is famously known as the ‘polar bear capital of the world’ due to the Western Hudson Bay population that pass through the town each summer and autumn.

Polar bears often seek out human settlements for food

Between the 1940s and 1980s, these bears regularly visited a waste disposal site, feeding on scraps that caused property damage, human injuries, and malnutrition for the bears. The food waste was often insufficient in fat and contaminated with plastics, metals, and wood. 

Efforts to manage the problem included better waste management, relocating bears, temporarily housing them at a holding facility until Hudson Bay froze, or, in some cases, lethal removal.

The Government of Manitoba has since closed the dump site and established the Polar Bear Alert Program to minimise the need for lethal measures and reduce conflicts with bears.

As polar bear encounters become more frequent, the significance of this program is expected to grow.

How orcas and Arctic foxes hunting impact communities

Sometimes predators feed on animals of economic and ecological importance to people. These are depredation events (events that cause damage or destruction).

Depredation events often happen in the polar regions. Posted by Ocean Generation

Mammals in the Arctic Ocean are increasingly observed preying on fish caught by commercial and recreational fishing boats. Longline fishing, which involves the use of baited hooks on a long line, is currently the most severely affected by depredation across both hemispheres, primarily by toothed whales, such as orcas and sperm whales.

These depredation events can result in financial losses for fishers who face difficulties due to reduced catch and often face costs for repairing damaged fishing gear. These interactions can also harm wildlife through injuries or fatalities caused by entanglement with fishing gear and responses from fishers.

Orcas, otherwise known as killer whales, are frequently involved in depredation events in polar regions. It’s been suggested that their group hunting behaviour enables orcas to effectively remove fish from longlines.

These animals are highly social and live in tightly knit family groups, known as pods. Research suggests that pods which overlap geographically can communicate and share information. It’s thought that this cultural transmission is causing depredation behaviour to spread throughout western Alaska.

Depredation on land is also a concern, particularly with Arctic foxes preying on reindeer calves

In the Yamal Peninsula, traditional reindeer herding practices are central to the lives of the indigenous Nenet people of Arctic Russia. However, reindeer mortality has increased due to factors such as pasture icing (explained later), disease outbreaks, and predation by Arctic foxes.

Arctic foxes prey on reindeer calves in Arctic Russia

The population growth of arctic foxes has been fueled by the collapse of the fur trade in the 1990s, which reduced hunting pressure. Industrial expansion also provided waste for foxes to feed on, further supporting their population increase.

Climate change worsens the issue by causing abnormal weather conditions, such as freezing rain and rapid temperature fluctuations, which lead to pasture icing. This occurs when a thick layer of ice forms over grazing land, trapping vegetation and making it inaccessible to livestock and wildlife. As a result, weakened reindeer become easier prey for foxes, while more carcasses are left for scavenging.

Finding solutions for people and wildlife

Human-wildlife conflict in the polar regions presents challenges, especially with the added pressures of climate change and other stressors.

However, finding solutions that harmonise conservation goals with community needs can lead to positive outcomes for both people and wildlife. Check out our article on Balancing Conservation and Community in Polar Wildlife Conflicts for strategies to effectively manage and resolve human-wildlife conflict.

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3. 10. 2024 Grace Cardwell

Why does the climate change?

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The Earth’s climate has changed naturally for billions of years, but human emissions are rewriting the story.

Scientists know that the Earth’s climate has always changed by itself, even before humans existed.

The climate changed in a pattern for the past 800,000 years. Every 100,000 years, the Earth entered a warm period, called an “interglacial”, lasting 15,000-20,000 years. Between these periods, ice ages called “glacials” dominated.

Changes to the climate that caused these glacials and interglacials in the past can be explained by natural forcings. These are forces that act upon Earth’s climate, causing a change in how energy flows through it e.g., greenhouse gases.

What are some natural forcings?

1. Milankovitch Cycles

Milutin Milankovitch, a mathematician, discovered three “Milankovitch” cycles.

Over the past 800,000 years, these were the dominant causes of climate variability because they affect the amount of solar heat that can reach the Earth’s surface.

Eccentricity occurs every 100,000 years, corresponding with interglacials. Sometimes Earth’s elliptical orbit is more circular, which keeps the Earth at an equal distance from the Sun. When the orbit is more elliptical, Earth’s distance from the Sun changes. When Earth is closer, the climate is warmer. 

Obliquity, Earth’s axial tilt, changes between 22.1° to 24.5° every 41,000 years. Larger angles cause warmer summers and colder winters.  

Every 19,000 – 24,000 years, Precession impacts seasonal contrasts between the hemispheres and the timing of seasons. The Earth wobbles on its axis due to the gravitational pull of the Sun and moon, changing where the North Pole points. 

Milankovitch cycles are long term changes that affect the climate — *Design by Grace Cardwell*

2. Sunspots

Every 11 years, the Sun gets spots when its magnetic field increases. The temperature is lowered in this area, influencing the amount of solar radiation warming Earth.

3. Changes in Ocean currents

Ocean currents carry heat around the Earth. When the Ocean absorbs more heat from the atmosphere, sea surface temperatures increase, and Ocean circulation patterns change. Different areas become colder or warmer. 

Because the Ocean stores a lot of heat, small changes can have massive effects on the global climate. A warmer Ocean can’t absorb as much carbon dioxide (CO₂) and will evaporate more water vapour. Both contribute to the greenhouse effect and global warming.

4. Volcanic eruptions

Volcanoes spew out sulphur dioxide and ash, which blocks solar radiation and cools the atmosphere. CO₂ released in the eruption eventually overpowers this to increase temperatures, but this is only equivalent to 1% of human emissions.

5. Meteorite and Asteroid impacts

66 million years ago, an asteroid hit the Earth on Mexico’s Yucatán Peninsula. Scientists call this the Chicxulub Impact, and it drove the extinction that killed 60% of all species, including all non-flying dinosaurs.

Lots of sulphur, soot and dust entered the atmosphere, blocking out the Sun. Temperatures plummeted 15°C, causing a 15-year winter.

Natural forcings explained by Ocean Generation.

Some climate change and emissions are unavoidable.

But natural forcings are too gradual or irregular to cause current climate change.

The Intergovernmental Panel on Climate Change (IPCC) states “the observed widespread warming of the atmosphere and Ocean, together with ice mass loss, support the conclusion that it is extremely unlikely that global climate change of the past fifty years can be explained without external forcing, and very likely that it is not due to known natural causes alone”.  

Just right or too hot?

Greenhouse gases are natural, to an extent.

Some solar radiation passes through the atmosphere, hitting the Earth. Most of this is reflected into space, but some is absorbed by greenhouse gases and re-directed back to Earth.

This keeps Earth just right (Earth is called the “Goldilocks” planet!).

People are emitting too many greenhouse gases, too quickly. Therefore, more heat is trapped in the atmosphere, leading to global warming.

Greenhouse effect explained: normal and rampant CO2 — *Credit: National Park Service*

How are people causing climate change?

“External forcings” are things we’re doing that release extra greenhouse gases.

1. Power

We burn fossil fuels like coal, oil and gas to make electricity and heat. This releases carbon dioxide and nitrous oxide to the atmosphere. Half of this electricity powers our buildings.

Globally, only about ¼ of our electricity comes from wind, solar and other renewable sources.

Some people use more power than others: the richest 1% of the global population combined account for more greenhouse gases than the poorest 50%.

2. Food and Manufacturing

To make goods like steel and plastic, fossil fuels are burnt to power factory machines and many other processes. Manufacturing is one of the largest contributors to greenhouse gas emissions worldwide.

Food production emits greenhouse gases at various stages. Livestock and rice farming releases methane, fertilisers release nitrous oxides, and carbon dioxide is released to make packaging and transport the food.

How are people causing climate change: Explained by Ocean Generation.

3. Deforestation

In places like the Amazon Rainforest, trees are cut down to make space for farming and houses. From 2003 – 2023, 54.2 million hectares of rainforest was lost there.

When trees are cut down, they release locked up carbon. With fewer trees, less CO₂ absorption can take place. Land use changes make up ¼ of greenhouse gas emissions.

4. Transport

Cars, ships and planes all burn fossil fuels such as petrol. This makes up ¼ of global energy-related CO₂emissions. This graph shows our impact on the atmosphere:

This graph shows our impact on the atmosphere.

Don’t put the blame on natural forcings.

Now we know current climate change is down to us; everyone has a responsibility to reduce their emissions. Have a look and see what you can do!

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30. 09. 2024 Grace Cardwell

What can Antarctic ice cores tell us about the history of our climate?

What can Antarctic ice cores tell about the history of climate

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Ice cores are the key to the ancient climate and can help us unlock the mysteries of the future.

Scientists can drill into ice sheets to obtain a cylinder of ice, called an ice core.

Ice cores are “time capsules” of the climate. Over time, annual and seasonal snow with different chemical compositions, particulates (like dust), and bubbles of air are compressed into ice.

What-can-Antarctic-ice-cores-tell-about-the-climate — *Credit: Bradley R. Markle via Eos*

Scientists are asking the core questions.

One of Antarctica’s ice cores, Dome Concordia, shows the climate record for the past 800,000 years through the Quaternary period (2.58 million years ago – present).

Annual temperatures are estimated using oxygen’s heavy (O¹⁸) and light (O¹⁶) varieties, called isotopes. When atmospheric temperatures increase, more energy is available to evaporate water containing more O¹⁸from the Ocean. This water is precipitated in Antarctica and turns to ice. Scientists can relate the isotopic ratio in an ice layer to the temperature.

Trapped air is analysed for which/how much atmospheric greenhouse gases were present annually. Scientists can estimate carbon dioxide (CO₂) and methane (CH₄)to determine the degree of global warming.

Using this data and more, scientists can piece together past climates.

Ice cores are key to ancient climate: Explained by Ocean Generation.

What’s the story, ice cores?

Ice cores tell us that the climate swings between stable bounds of warm interglacials happening every 100,000 years which last 15,000 – 20,000 years, and cold glacials (ice ages).

Ice cores show these key events:

1. 800,000 years ago in the Pleistocene, ice cores show an interglacial Earth. The glacial-interglacial pattern continued from here…

2. 430,000 years ago, the Mid-Brunhes Event marked the sudden increase in the temperature range of climate cycles.

3. The penultimate deglaciation event, seen in Antarctic ice cores extends from 132,000 -117,000 years ago.

4. From 24,000 – 17,000 years ago, the Earth was glacial, with temperatures 20°C below pre-industrial levels.

5. Deglaciation began 16,900 years ago, punctuated with tiny ice ages, called the “Bøllering-Allerød” and “Younger Dryas”, thanks to the “bi-polar seesaw” (the Northern Hemisphere cools whilst the Southern Hemisphere warms and vice versa).

6. 15,000 years ago, ice sheets began to shrink. This heating continued into the Holocene (the official period of geological time which we currently live in)

7. This interglacial’s temperature peaked between 14,500 and 14,000 years ago.

What ice cores tell us about ancient climate.

8. From 13,800 – 12,500 years ago, Antarctica experienced a Cold Reversal, where temperatures plummeted.

9. The Holocene interglacial began 11,000 years ago, with temperatures fluctuating between warm and cold again.

10. 1,000 years ago, the Medieval Warm Period allowed crops to flourish, cities to rise, and populations to more than double.

11. The Little Ice Age, from the 14^th-19^th centuries, caused Viking colonies in Greenland to fail.

12. 1750 – the Industrial Revolution began. Ignorant to environmental consequences, humans started emitting greenhouse gases.

13. Scientists mark 1800 as initiating the Anthropocene, an unofficial epoch where humans effect the climate more than natural forcings.

14. Humans have continued global warming at an unprecedented rate. Summer 2024 was the world’s warmest on record. August was the 13^th in a 14-month period where global average temperatures exceeded 1.5°C above pre-industrial levels.

Antarctic ice cores timeline of events _ Ocean Generation Download

Is the past a mirror of the future?

Levels of greenhouse gases are higher than in the past 800,000 years, with average CO2 at 419.3ppm as of 2023.

Paleoclimatology records like ice cores and marine sediments help scientists to understand past climates and estimate future climates. They can compare different emission scenarios with the past to see how future climates may respond.

The Intergovernmental Panel on Climate Change (IPCC) have estimated several trajectories.

The aggressive mitigation scenario expects CO₂ concentrations to remain at Pliocene-like concentrations (>350ppm) until 2350. It will still take 100s -1000s of years for concentrations to return to pre-industrial levels.

Under a middle-of-the-road scenario, CO₂ peaks at 550ppm, remaining above Pliocene levels for 30,000 years.

If CO₂ reaches 1000ppm, the worst-case scenario suggests concentrations will remain at Mid-Cretaceous levels for 5000 years, Eocene levels for 10,000 years, and Pliocene levels for 300,000 years. It will take 40,000 human generations for CO₂ to return to pre-industrial levels.

Are past climates mirror of future events? — *Credit: International Geographical Union*

Scientists and governments can then prepare for the extreme consequences of climate change and make net-zero emission targets.

Although the Earth has recovered in the past, the future is uncertain. What will happen to our Ocean and our species? We all have opportunities to ensure a “best-case scenario”.

Antarctic ice cores unlock the past, our actions will unlock the future.

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27. 09. 2024 Grace Cardwell

Why the Arctic is the fastest warming region on the planet

The changing Ocean climate: Why the Arctic is the fastest warming region

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A polar biome brimming with glaciers, permafrost, and sea ice. Home to countless species, but for how much longer?

The Arctic is extremely sensitive to environmental changes. The increase in global mean air temperature is linked to the excessive melting of Arctic sea ice: one of the most unambiguous indicators of climate change. Since 1978, the yearly minimum Arctic sea ice extent has decreased by ~40%.

Global warming is rapidly taking place due to our greenhouse gas (like carbon dioxide (CO₂)) emissions. Our current emission rates of ~40 Gt CO₂/year could leave the Arctic ice-free by 2050.

Our Ocean also plays a role in climate change.

Barents Sea is the hotspot of global warming: Explained by Ocean Generation

“The hotspot of global warming” – not the nickname you want!

Unfortunately, this is the nickname the Arctic’s Barents Sea is bestowed. Atlantification (the process by which the warming climate alters the marine ecosystem towards a more temperate (milder) state) is to blame.

Scientists (though they’re still not 100% sure of all processes involved) have noticed drastic changes in our Ocean where Arctic and Atlantic conditions collide.

Arctic water is colder and less salty than Atlantic water. Thawing ice releases freezing freshwater into the Ocean, keeping Arctic water buoyant. Atlantic water, being warmer and more saline, should sink beneath Arctic water, creating a salinity gradient called a halocline.

The halocline protects ice from thawing by blocking warm water from rising.

However, because atmospheric temperatures are increasing and melting the ice, and less ice is imported into the Barents Sea, freshwater supplies are dwindling. This disrupts the halocline. Surface winds stir up the Ocean, drawing Atlantic heat upwards to melt the ice.

Atlantification
and the Arctic halocline explained by Ocean Generation. — *Design by Grace Cardwell*

Throughout the 2000s, the Barents Sea experienced a 1.5°C warming of the upper 60m of its water column, with sea ice thickness decreasing by 0.62m/decade.

Plenty of fish in the sea – but are they the right ones?

Birds are indicators of a changing marine ecosystem.

After hot winters in Kongfsjord (Norway), Black Legged Kittiwake diets shifted in 2007 from Arctic cod to Atlantic capelin and, as of 2013, herring as their main meal. Whilst Kittiwakes seem to have adapted to their new diet, some species aren’t so lucky…

The most abundant sea bird in the North Atlantic, the Little Auk, should eat Arctic zooplankton.

The Little Auks decreased in fitness (the ability to survive and reproduce in a competitive environment) due to Atlantic water inflow. Chick growth rate decreased from six to five grams per day when Atlantic water inflow increased between 5-25% in Horsund (Norway).

Atlantic zooplankton are a suboptimal food source for the Little Auk because they provide less energy than Arctic zooplankton. Because there is less Arctic prey, chick parents spend time and energy foraging for it and might favour their own maintenance over their chicks.

Scientists anticipate the Arctic will have the largest species turnover globally, predicting a northward marine fish species migration of 40km/decade. Atlantic species are already outcompeting Arctic species, which could lead to extinction and changes in the food web.

Could the killer whale overthrow the polar bear, which has reigned as the top Arctic predator for over 200,000 years?

Feedback. But not the helpful kind…

In 1896, scientist Svante Arrhenius noticed that Arctic temperature changes were higher relative to lower latitudes. This is known as Arctic Amplification and has occurred for over three million years.

The main driver of this is the albedo effect. This effect is a positive feedback mechanism, where the result of the mechanism causes the mechanism to repeat itself – in a loop.

Dark objects absorb 93% of the sun’s energy. When the Arctic receives solar radiation in the spring, melting ice, darker areas are exposed amongst the ice which absorb more solar radiation. This reveals the even darker Ocean, repeating the loop.

Melt seasons are becoming longer as a warming climate leads to an earlier spring melt and exposes darker areas for longer. The Barents Sea’s ice-free season increases by 40 days per decade.

Where ice has melted, vegetation replaces tundra. Plants are darker than ice, so this furthers the albedo effect. Permafrost also melts, releasing CO₂ and methane (which has 84x the warming effect of CO₂in the first 20 years after its release), contributing to the greenhouse effect and exposing darker ground.

Since 1979, the Arctic has warmed
nearly four times faster
than the rest of the globe. Posted by Ocean Generation, leaders in Ocean education.

We are amplifying these positive feedbacks with greenhouse gas emissions. Since 1979, the Arctic has warmed nearly four times faster than the rest of the globe, with the most Arctic Amplification observed in autumn and winter.

Positive feedbacks are taking place very quickly, perhaps too quickly for negative feedbacks (like cloud cover) to balance them. Scientists are uncertain about future trajectories.

In the past, the Palaeocene-Eocene thermal maximum saw an ice-free Arctic. Is this a mirror of the future?

What can be done to slow down Arctic warming?

Local knowledge aids global governance and monitoring of organisms and landscapes.

Regional plans like Alaska’s 2017 “Climate Action for Alaska” set targets for reducing emissions.

Canada’s ArcticNet scheme distributes knowledge for policy development and adaptation strategies, helping Canadians face the challenges and opportunities of socio-economic and climate change.

The Arctic Council involves international cooperation towards marine and science research. Arctic and non-Arctic states, indigenous representatives and NGOs engage in binding agreements, for example: committing to enhance international Arctic scientific cooperation.

On a smaller scale, the Arctic Ice Project wants to spread silica beads across the ice to increase reflectivity.

But it’s clear: further global cooperation is needed. In 2015, The Paris Agreement stated that temperatures shouldn’t rise 2°C above pre-industrial levels, yet global warming is continuing.

Barents Sea is the hotspot of climate change: Explained by Ocean Generation

What can we do?

Every tonne of CO₂ we emit melts three m² of Arctic sea ice in the summer.

To reduce emissions, hold yourself, your country, and the businesses who produce the goods you consume accountable. Walk instead of drive. Switch off lights. Support others fighting for the Arctic.

Don’t just leave it to the scientists. The Arctic isn’t a disappearing, far-away land. Your help, regardless of scale, is necessary for our Ocean to thrive.

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21. 08. 2024 Olivia Jones

Why do marine animals migrate: Everything you need to know

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Migration across the Ocean is such an extraordinary phenomenon that scientists today are still trying to discover how and why it’s done.

How does a turtle find the same exact beach where it hatched after an epic journey across the Ocean?
How do gray and humpback whales navigate record-breaking migrations: 14,000 miles of deep blue sea over 172 days?
Why do sardines, whales, turtles, hammerheads, great whites, manta rays and all manner of smaller creatures undertake these incredible journeys across our seas?

Why do marine animals migrate across the open Ocean?

Crossing an entire Ocean is extremely tiring. You could get lost or caught in a storm and you’re exposed to various risks along the way, so why do it?

Migration comes down to a need for a resource that an animal doesn’t have in its current environment. They’re often seasonal, long-distance movements in search of food, mates, habitat or to escape predation.

Long journeys across the Ocean come with many challenges for migrants. Posted by Ocean Generation, leaders in Ocean education

Food: One of the biggest reasons for migration.

Baleen whales, like humpbacks and gray whales, will migrate to northern latitudes during the spring and summer to feed in cold arctic waters, rich in krill and shrimp like crustacea. The long, tiresome journey from the south is made worthwhile for the feast of food that awaits them there.

Turtles also make their way north, with species like leatherbacks spotted in the waters off Canada, Alaska or Nova Scotia. Leatherbacks are some of the most highly migratory animals on Earth, the longest recorded journey being 12,744 miles from Indonesia to Oregon, USA.

Here during the summer months, there is an increasing abundance of a turtle’s favourite food: jellyfish.

But of course, the food can move too.

Fish are one of the most important sources of food on Earth, preyed upon by numerous different animals, including humans. The KwaZulu-Natal sardine run, also known as the “greatest shoal on Earth,” is a mass migration of South African sardines to the sub-tropical waters of the Indian Ocean.

Sardine run is a mass migration of South African sardines in the Ocean — *Image credit: Mark van Coller/Solent News*

Estimated to rival Africa’s wildebeest migration as being the largest biomass migration on Earth, this shoal becomes a ‘moveable feast’ for opportunistic predators like sharks, dolphins, gannets, seals and whales.

Whales also migrate to find a mate.

Whales, like humpback and gray whales, feed in cold arctic and sub-arctic waters but that’s not a suitable place to find a mate and give birth to their offspring. They could breed here but there are serious risks to the mothers and their calves with the cold water and predation by animals like orcas.

Instead they move from north to south during the winter months, giving birth to their young in shallow, warm waters such as lagoons. Popular destinations include Baja California, Mexico, Hawaii and Japan.

Frodo the humpback whale, named after the Lord of the Rings character, underwent his record-breaking adventure to find a mate from the Mariana islands to Mexico covering around 7,000 miles. Check out his journey on Happywhale.

Whales migrate thousands of miles across the Ocean. Posted by Ocean Generation — *Map of Frodo’s travels from Happywhale.com*

Humpbacks will often migrate the same routes they were guided on by their mothers. Frodo’s unusually long journey may be relic behaviour of the whaling industry, where depleted numbers require males to travel further in search of a mate.

Turtles will return to the exact same beach where they hatched to lay their eggs, known as natal homing. Most turtle species spend most of their time in the open Ocean, widely dispersed across the globe.

But how do they know where they are and where they’re going?

Turtles show remarkable navigation skills with pinpoint accuracy using a combination of external cues to calculate their position and route. When they are near the site of their hatching, turtles may use visual cues such as the incline of the beach or the smell of the water or air.

However, in deeper water turtles must resort to other methods to find their way home. Loggerhead, green and leatherback turtles have all demonstrated the use of a ‘magnetic map sense’ like other long-distance migrants such as bird and butterflies.

Along a coastline, the inclination and intensity of the magnetic field will vary, giving rise to a unique magnetic signature at a precise location. Scientists suggest that hatchlings imprint on this unique magnetic signature and use it to navigate back across the entire Ocean years later.

Sea turtles have remarkable navigation skills to migrate across the Ocean

Long journeys come with obstacles that Ocean migrants must face.

Our Ocean is becoming an increasingly treacherous place for its inhabitants, with threats from entanglement, ship strike, lack of jurisdictional protection and climate change.

As these migrants make their way along vast journeys, they tend to cross paths with one of the most dominant and widely distributed animals on Earth: people.

Many important migratory routes for whales and other surface-dwelling animals like turtles and sharks, converge with areas of heavy maritime traffic. This cross over can lead to ship strike, which is harmful if not fatal to an animal.

Species like the endangered North Atlantic Wright whale are particularly vulnerable as their habitat and migration routes are close to major ports and shipping lanes. There were 37 whales were reported injured in this region between 2010 and 2014 and that is likely to be an underestimate.

Furthermore, about 640,000 tonnes of discarded fishing gear, known as ‘ghost gear’, enters our Oceans every year, posing the major threat of entanglement.

The animals who travel the most are at higher risk of such encounters. For instance, an estimated 30,000 whales and dolphins die from entanglement each year.

Rising sea surface temperatures due to climate change may also alter where migratory species find food and push them past their heat tolerance. This could disrupt the longstanding migration patterns between feeding and breeding grounds.

Humpback whales migrate to warmer waters in the Ocean to breed

Nevertheless, there’s a push for the conservation of these migratory species and a desire to make the Ocean a safer place.

We’re constantly developing new technologies to help prevent animals from becoming entrapped in fishing gear. For example, Galvanic Timed Releases (GTRs) involve materials that disintegrate over time, opening doors or panels on the gear or allowing lines to break away.

Restrictions such as vessel speed limits and altered ship routes help avoid collisions with endangered species such as North Atlantic wright whales, as well as establishing temporary precautionary zones around recently sighted whale groups.

The migration of these marine travellers across the Ocean highway are some of the most extraordinary and treacherous journeys in the world.

Continuing to learn and understand these journeys is essential for protecting Ocean life and reducing the threat that is posed by humans.

Post by

Olivia Jones

Why are rivers important?

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9. 08. 2024 Jemma Sargeant

Re-thinking the shark stereotype

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With torpedo-shaped bodies, forked tails, and dorsal fins, sharks belong to a group known as cartilaginous fishes (meaning their skeleton is made from cartilage, not bone).

As one of the oldest evolutionary groups, the earliest fossil evidence for sharks or their ancestors’ dates to 400 – 450 million years ago.

This means that the earliest sharks may have been around before trees even existed (trees evolved around 360 million years ago).

What makes sharks unique?

Sharks are one of the most diverse groups of predators in the animal kingdom. They come in all shapes and sizes. Sharks can have huge, gaping mouths (like the basking shark), long whip-like tails (like the thresher shark) or flattened, club-like heads (like the hammerhead shark).

The largest species is the whale shark, reaching lengths of 20m. The smallest is the dwarf lanternshark which grows to just 20cm long.

It’s this diversity in shape, size, feeding mechanism and habitat that has enabled sharks to persist throughout all parts of the Ocean over millions of years. They even live in some freshwater environments.

Why are sharks important?

Sharks can play many roles in ecosystem functioning: from predators to prey, competitors, and nutrient transporters.

Some species of shark are apex predators, meaning that they’re at the top of their food chain and exert a top-down control on food webs. Others can sit further down the food chain, yet still play an important role as food for other predators and transporting energy through ecosystems.

Large scale movements and migrations of sharks also connect even the most widely spaced food webs, transporting nutrients across the open Ocean system.

Unfortunately, sharks are heavily misunderstood.

Media and popular culture often demonise sharks, portraying them as senseless killers through sensationalistic headlines and striking imagery. This is designed to incite fear, leading us to believe that the threat posed by sharks is greater than it really is.

Did you know? Our fear of sharks originates from the ‘Jaws Effect’. It’s the powerful influence of the famous 1975 Hollywood thriller on our human perception of risk from sharks.

Put simply: Few animals are feared more than the shark.

Some sharks are at the top of the food chain

But in reality, sharks have much more to fear from us than we do them.

The probability of a shark biting a human is very low compared to many other risks that people face in their everyday lives. According to the International Shark Attack File, there were 69 unprovoked shark bites, including 10 unprovoked shark-related deaths globally in 2023.

To put this into perspective, on average, 500 people are killed by elephants each year.

Sharks don’t actively hunt humans. The most common shark incident is known as a ‘test bite’. It means sharks swim away after a single bite once they realise it’s not their preferred prey. Surfers and other board sports make up 42% of reported incidents, as the shape of their boards can bear a resemblance to seals and other prey from below.

When we do encounter sharks, it’s often because their natural behaviour clashes with our activities, from fishing to recreation.

In contrast, the global population of sharks and rays have plummeted by over 70% over the past 50 years.

The pressure on shark populations continues to rise. At least 80 million sharks are killed each year and over 1/3 of all shark and ray species now threatened with extinction.

To put that into perspective, there are only 19 countries in the world whose population is greater than 80 million. As of 2024, the number of sharks killed each year exceeds the total population of Thailand (71.8 million), the UK (68.3 million), and France (68.1 million).

Sharks are particularly vulnerable to overexploitation.

They grow slowly and take a long time to reach sexual maturity.

Shark mothers put a significant amount of energy and time into the development and care of their offspring. They also take extensive rest periods between pregnancies.

This makes sharks far less resilient and slower to recover from disturbance and overexploitation than other fish species.

Overfishing is the greatest threat to shark populations worldwide.

The 70% decline in shark and ray populations is largely attributed to an 18-fold increase in fishing pressure over the past 50 years.

A key incentive for shark fishing is the Shark Fin Trade. This is the practice of removing the fins from a captured shark and discarding the rest back into the Ocean. Shark fins have become one of the most valuable seafood products worldwide, and this globalised market exists largely to meet the demand for the traditional dish: shark fin soup.

However, despite widespread legislation designed to prevent shark finning in recent years, fishing pressure and shark mortality continues to rise.

Sharks are vulnerable to overfishing. Posted by Ocean Generation: We're rethinking the shark stereotype

Restrictions surrounding the practice of shark finning has driven up the appetite for shark meat. It’s because it’s often only illegal to land fins with the shark removed, not the whole animal. As a result, largely unregulated fisheries in the high seas continue to put pressure on global shark species.

These markets are muddied by misidentification (often of protected or endangered species). For example, in Brazil, the meat is labelled “cação”: an umbrella term under which both shark and ray meat are sold.

This lack of transparency leads to consumers being poorly informed, and they often aren’t aware that the animals on their dinner plate are at risk of extinction.

Scientists used satellite tracking to discover that about 24% of the area sharks use each month overlap with large-scale industrial fishing zones. This means that many shark species in the open Ocean spend almost ¼ of their time under the looming shadow of large-scale fishing fleets.

Climate change compounds these threats.

The Ocean’s oxygen minimum zones (naturally occurring areas of open Ocean low in oxygen) have expanded horizontally and vertically. This is due to higher temperatures and changing circulation patterns associated with climate change.

The expansion of these oxygen minimum zones has caused the habitat of oceanic sharks to be compressed towards the surface, since they can’t survive in low oxygen conditions.

Species like the blue shark are being pushed closer towards intense surface fisheries as a result, making them more vulnerable to being caught as bycatch.

Sharks diversity has enabled them to persist through millions of years. Posted by Ocean Generation: We're rethinking the shark stereotype

Despite the alarming statistics, it’s not all bad news for sharks.

In the northwest Atlantic, the white shark appears to be recovering after a 70% decline over the past 50 years, and hammerhead shark populations are also rebuilding here. This success is owed to strictly enforced fishing bans and quotas throughout their range.

This gives us hope that the successful implementation and enforcement of science-backed management across a species range can reverse shark population declines.

To protect sharks, we need to change the way we think about them.

Our irrational fear of sharks is limiting support for their conservation.

When we portray sharks in a negative light, our sense of risk becomes heightened. This leads people to believe that extreme mitigation measures such as culling are not only appropriate, but necessary.

This fear also diverts our attention away from the species which are at the highest risk of extinction and ignores the ongoing threats to sharks and their habitats.

Sharks have survived all five previous mass extinction events. For them to survive the sixth, we must re-evaluate our perceptions of them and show our support for the conservation of these magnificent creatures.

Post by

Jemma Sargeant

Why are rivers important?

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Why are rivers important?

From the creek whispering through a forest, to the confusion of huge currents twisting against each other in the channel. Rivers take on many forms. They are the direct connection between us and the Ocean but why are rivers important?

What are rivers?

Which is the biggest river?

River origin leads to debates over which the longest river is – the Nile or the Amazon.

Next, there is the deepest river in the world: the river Congo.

The Amazon stands alone in the amount of water it gathers.

Where are estuaries?

But why do rivers matter?

How do rivers change the world?

How are rivers and estuaries important for us?

What are the threats to the rivers?

How does pollution affect rivers?

How are estuaries under threat?

How can we look after our rivers?

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COP29 outcomes: Wins and disappointments

COP29 finished on the 24th November 2024, after two weeks of tough, technical negotiations.

Money, money, money.

What were the themes of COP29?

Presents and petrol stations.

Should discussions around climate change happen in the house of the industry most responsible for the damage?

Activism has always been a big part of COP.

COP29: Agreements and outcomes.

The reaction to COP29 has been, optimistically, mixed.

Outside the negotiating rooms.

What happened at COP16 (the biodiversity summit)?

At COP16, the Ocean was prominent in a way not previously seen.

COP29 and COP16: the transition from negotiation to actions.

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Everything you need to know about COP: COP29, COP16s and the things between

Heard a lot about the COP conferences but not sure what’s going on? Acronyms got you all in a twist?

What is COP?

Why are there multiple COPs?

The most famous COP outcome was the Paris Agreement.

What does COP mean for the Ocean?

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How Climate Change threatens polar species: Polar bears, Orcas and Narwhals

Many polar species depend on sea ice for essential activities like resting, hunting, and avoiding predators but climate change poses a threat.

How polar bears are impacted by climate change

How narwhals are impacted by climate change

How orcas are impacted by climate change

Many Arctic marine species use frozen areas as a refuge from orcas.

Turning climate challenges into opportunities

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Surviving the Polar Regions: Animal strategies and adaptations

The polar regions are among Earth’s most unique environments

Where is the Arctic? Where is the Antarctic?

Slow and steady is key to survival.

How species cope with food scarcity in the polar regions

How species cope with freezing temperatures

Behavioural adaptations also play a key role in survival

Snow place like home

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Balancing conservation and community in polar wildlife conflicts