Marine heatwaves - an ever growing threat?

Hi everyone,

So today we're talking about marine heatwaves. We all know about normal heatwaves, they come almost every summer and are either a blessing or a curse depending on where you live. But today we're talking about marine heatwaves. They are increasing rapidly and have become a commonly mentioned topic.

There are multiple definitions of marine heatwaves. Generally, they are considered a period of time with unusually high temperatures. Exactly how high and for how long changes depending on which definition you choose. The most common one definition is when the temperature is over the 90th percentile of the area's average seasonal temperature for at least 5 days in a row. For anyone who doesn't know what a percentile is, if you take a test and are at the 90th percentile then it means you are better than 90% of the people who took that test. So in our context, the temperature has to be higher than 90% of the seasonal temperatures measured in that area (normally over a 30 year period) for at least 5 days.

So what are the impacts of such an increase in temperature? Surprise surprise: marine heatwaves aren't exactly good for the environment. It is worth mentioning here, that marine heatwaves are natural occurances in the ocean temperature and have always been around. But the frequency and intensity of them is not natural. Both of these parameters have been rising rapidly in the last 100 years. Marine heatwaves can cause waters to reach temperature of 30°C, which is about the temperature of a warm bath. El Niño, a weather cycle that repeats about every 7 years, is shown to cause stronger heatwaves.

In the late 1990s, a marine heatwave intensified by El Niño lead to a reproductive failure and mass mortality in Galápagos sea lions and king penguins. Then, in 2011, the western coast of Australia was hit by a marine heatwave that caused the mass dieback of kelp forests and impacted ecosystems hundreds of kilometers further along the coast. An interesting phenomen was seen here, when several fish species changed their habitat and spread further towards the poles. This has been seen a couple time since in multiple species, sometimes the fish return once the waters have cooled, sometimes they stay in their new home and sometimes they die, either from new predators or a lack of food.
In 2014-2016, the northeastern Pacific saw mass mortality in seabirds as they failed to adapt to soaring temperatures. In 2017, there are reports of mass mortality affecting 40 coral reef fish species correlated with an increased risk of bacterial infection and harmful algal blooms, which produce toxins. And finally, in August 2020, a marine heatwave in the East China Sea caused a major typhoon in that area. The East China Sea rarely experiences typhoons and normally those that come in from the Pacific tend to die down, but this time the high surface temperatures caused a typhoon of Category 3.
There are some postives, mussels have been found to be able to change their heart rate so as to better deal with higher temperatures. This is just one example of how amazing and resilient nature can be.

So marine heatwaves are clearly a massive problem. As you can imagine, typhoons and collapsing fish populations are also a bit of a disaster for us. These marine heatwaves will only continue to become more frequent and more devastating as climate change warms up our oceans. We couldn't cover all of the aspects in this post so let us know what we missed in the comments. We hope this was a good introduction in this complex topic. Have a nice weekend!

Your Green World Blog Team💚

Sources:
https://www.nature.com/articles/s41612-023-00449-5
https://www.annualreviews.org/doi/10.1146/annurev-marine-032122-121437
https://en.wikipedia.org/wiki/Marine_heatwave
https://www.sciencedaily.com/releases/2023/09/230921105743.htm

Image:

Title image: This image is owned by a blog editor.
"Galapagos sea lion", owned by Darek Keats (on flickr.com), is licensed under CC BY 2.0.
"Baltic blooms", owned by European Space Agency (on flickr.com), is licensed under CC BY-SA 2.0.

Comments

April Top Tips: ten tips for environmentally friendly travel

Hi Everyone! We haven't been very present on the blog again recently but we are back today with ten top tips for environmentally friendly travel. Most forms of travel over long distances (unless you are willing to put in a lot of physical effort) use fossil fuels and are generally not good for our planet. So today we will be giving you a few tips which although won't mean that your travel is 100% planet friendly, will be a good start to doing as much as you can. Your Green World Blog Team💚 1. Use trains and boats rather than planes where possible Planes are awful for the environment. They are, however, extremely practical and so easy to use, cheap...It's hard to avoid them! They are so quick too so you don't have to spend as much time travelling. However, they are really bad for the environment. For example, you could fly once to Edinburgh from Heathrow for the same carbon dioxide levels as driving to Edinburgh 336 times! 2. Fly...

Discussion || Should Everyone Switch To Electric Cars?

Hi Everyone! Thank you so much for joining me today, as I hop on the blog to discuss whether everyone switching to electric cars would really help the environment. In other words, should everyone switch to electric cars? This is the first part of a two-part series, discussing electric cars, so stay tuned for part two!! I would like to start this post by stating that I am by no means an expert. This is knowledge I have from my own experience, and from research I have done. If anything is incorrect please take it as it is and accept that this is a discussion and I am taking on board all opinions from reliable sources on this complex topic. Electric cars are a huge topic when it comes to sustainability and "saving our planet". There is no debating the fact that electric cars are better for the environment than diesel or petrol once they are on the road. But the production of them is often very polluting, with one study show...

Ozone layer

Hi everyone, What even is ozone? And the ozone layer? Where does the hole in the ozone layer come from and what does it mean? Is it dangerous? What can be done? Often the ozone-talk can be complicated and confusing, keeping an overview is hard and understanding all the problems always difficult. Let us break it down a bit for you: What is the ozone layer? We'll start with the basics: The ozone layer is part of the stratosphere, which is the second layer of the Earth's atmosphere, between 10 and 50 km above the Earth's surface and made up of protective gases. One of these protective gases is ozone. There is not much ozone in the atmosphere, only 0.3 molecule of ozone per 1 million molecules of air. This is because ozone is chemically unstable and only forms when ultra violet radiation (UV light) hits oxygen and breaks the bonds between the atoms. It fact it is so unstable that even when it has formed, it breaks down again relatively quickly. This leads to ozone turning back ...

Photo Essay | dolphin spotting boat ride

Hi Everyone! Quite a while ago now, me and my family went on a dolphin spotting boat ride, and I've been meaning to share some photos for ages now! We saw so many dolphins very close up and we managed to get some good shots, although it can never be as magical as in person! All photos in this post were taken by me or my family. They were so close to the boat! This photo is stunning! It's under the water! Again - under the water! It was so hard to capture them jumping! This was the boat.... ...

Coral reefs

Hello! We would love to introduce you to the topic of coral reefs and especially coral reef bleaching, as it is a greatly ignored but certainly significant topic. Have fun! 5 coral reef facts 1. The Great Barrier Reef is the largest living structure on the planet and is 2300 km long! 2. Less than 0.1% of the world's ocean surface is covered in coral reefs. 3. At least 25% of all marine animals live there. 4. Coral reefs are often known as the rainforests of the ocean. 5. In 1 square kilometre of coral reef, up to 35 tons of fish can be 'produced'. The 5 biggest coral reefs in the world 1. Great Barrier Reef (near Australia) 2. Red Sea Coral Reef (near Egypt, Israel and Djibouti) 3. New Caledonia Reef (Pacific Ocean near New Caledonia) 4. The Mesoamerican Barrier Reef (near Mexico, Belize, Guatemala and Honduras) 5. Florida Reef (Atlantic Ocean/Gulf of Mexico near Florida) What is coral? Coral is actually made up of small anim...

Deforestation and why it’s a problem

Hi everyone, Welcome back to another post. Today we’ll be talking about deforestation and its impacts on our earth. Deforestation, the widespread clearance of natural forests, has been happening for thousands of years. One example is Western Europe, where, two millennia ago, 80% of the land was cloaked in dense forest cover. However, over time, a significant portion of this green expanse was sacrificed to create room for crops, livestock grazing, and as a source of fuel and building materials. Presently, a mere 34% of Western Europe retains its woodland. Today, the tropics deal with the brunt of deforestation. Activities such as mining, agriculture, road construction, and the establishment of vast cattle ranches drive the mass clearance of tropical rainforests. This results in the release of huge amounts of carbon dioxide into the atmosphere, exacerbating the global climate crisis. The consequences come in two waves: first, the reduced number of...

How well do you know intelligent animals? - Quiz

Hi everyone It's time for another quiz. Intelligence is necessarily restricted to humans. Many animals display signs of what we deem to be intelligence. Questions How many words have some crows been taught to say out loud? a) 20 b) 50 c) 100 Which signs of intelligence have been found in orangutans? a) tool use b) logical reasoning c) recognising themselves in a mirror True or False? An African gray parrot called Alex was trained to correctly categorise items into 13 colour categories. What do some particulary clever veined octopuses use coconut shells for? a) to play with b) shelter c) food True or False? Orcas can recognise themselves in a mirror. What have chimpanzees recently been observed treating their wounds with? a) insects b) tree sap c) fresh water How many nouns did an American border collie recognise and remember? a) over 500 b) o...

Ecotourism: what it is, the advantages and the disadvantages

Hi Everyone! Today we wanted to talk about the idea of ecotourism, including the advantages and disadvantages of this concept. If you are looking to reduce your environmental and social impact when travelling, then this is the post for you! Ecotourism is a form of tourism which limits the damage to the environment and local community. It can involve helping in community projects such as planting trees, as well as taking part in local customs and festivals. It helps to keep the local culture alive, while preserving the natural environment. The advantages are abundant. By helping in a project conserving the environment, tourists gain a new understanding and appreciation for the natural world and may be inspired to make changes in their "real" life to live more sustainably. It provides a valuable insight to a country and community, perhaps also inspiring more respect for different people and the lives they lead. The projects also provide sustainable income sources for locals, h...

Animals 36-40 in our '50 incredible animals' series

Hi, As you probably noticed, we took a break from this series, mostly due to having just too much to do. But we're back now with the last three posts. 36. The Pinocchio frog The Pinocchio frog can be found in the Foja Mountains in Indonesia. They mainly eat insects, although little is known about them. They are named because the males have a spike on their noses. They were only discovered in 2008, and this was completely by accident! It remained unnamed scientifically until over ten years later when it was given the name " Litoria pinocchio " . There is very little information about them but Wikipedia states that "the male Pinocchio frog inflates its nose when calling, and the nose decreases in size when the frog is calm and quiet," which I think is hilarious and so interesting! 37. Snub-nosed monkey Especially noticeable due to their curious looks, the snub-nosed monkeys can be found in the forests of central China and northern...

Animals 21-25 in our '50 incredible animals' series

Hi Everyone! Here are the next five animals in our current series! We hope you learn something from this. 21. Stick insect Stick insects are masters of disguise. They look like twigs or leaves. This strange appearance makes them hard to spot when stationary. Stick insects are herbivores, feeding on leaves, and can live for up to three years. Their habitat includes most tropical and subtropical regions, but there are a few species that live in temperate areas as well. There are roughly 3 000 different stick insect species! Not much more is known about them, because they are difficult to find. The two main threats to their populations are the pet trade and people killing them so as to frame their carcasses, like butterflies. Their conservation status ranges from critically endangered to least concern - so basically every category that is on the list! 22. Glass frog The glass frog is, well, see through. You can literally ...

Green World

Search This Blog