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

16.08.2020 Animal of the week: Elephant

Hello. On the 12th of August it was International Elephant Day, so we decided that this week's post should be about elephants. Elephants are the largest living land mammals. There are three types of elephant; the African bush elephant; the African forest elephant and the Asian elephant. African elephants have larger ears, whereas Asian elephants have smaller ears. Elephants use their trunks to breath, bring food and drink to their mouths and to grasp objects. Elephants' legs are like pillars. They carry the Elephant's massive weight. African bush elephants weigh 6000kg, Asian elephants weigh 4000kg and African forest elephants weigh 2700kg. Basically, they are very heavy.Elephants eat grasses, small plants, bushes, fruit, twigs, tree bark, and roots. Elephants can live up to 70 years old in the wild. They communicate by sight, touch and smell. Sadly, these wonderful mammals are in danger. African elephants are listed as vulne...

March 2021 Factfile - some news from the past month, animals that YOU voted for and more!

Hi Everyone! We hope you are all okay and will enjoy this month's wrap up post. We have managed to post a little more this month but we are off school soon so we may be able to post more! News! Recent European droughts and heatwaves are said to be worst in 2000 years The British newspaper, 'The Guardian' reports that the series of droughts and heatwaves since 2014 have been the worst in 2000 years. These heatwaves have disastrous consequences such as early deaths, crop failure and forest fires. For more information, click here . This is definitely the final bit of proof that climate change exists and that it needs to be stopped! Rise in deforestation in 2020 A horrifying 42 000 squared km of forest was chopped down in 2020, making it the third worst year since 2002. The most affected areas were humid tropical forests such as the Amazon, the Congo and other forests in South America and South-East Asia. These forests a...

Some info, resources & solutions to the plastic crisis

Hello Everyone, Plastic was once a miracle material but now it is the enemy. And we are the last generations who can do anything about it. If we want future generations to experience the world in all its amazing beauty like we have: we have to make a difference. We have the power to change the world for the better or for the worst. There will always be people who don't care about the environment but we do and so we need to do what we think is right. So join the campaign and fight for a better future. For our planet to return to its natural way with incredible biodiversity and amazing ecosystems. We have to make a difference now because all around the world animals are suffocating, drowning, and dying because of humans. You may think it isn't your problem but ultimately you are human and humans make plastic. Honestly, I can't believe that it has gotten to this point. We just have to change something because there is obviously something we ...

December Factfile

Hello, The fact file vote has come to an end and we have a winner. This year, we will be doing top tips. These will come out at the beginning of the month. These tips are, at the same time, challenges. We hope you will enjoy, and apply them! News Good news New hope for coral reefs A coral reef in India has been restored to health- the proof being in the noises the fish have been making. Many of these strange sounds have never been recorded before. This is amazing, especially considering that the reef has been devastated by blast fishing, where explosives are used to stun or kill everything in the area. Although the corals are being restored, scientists want to know if the animals are also returning and in what numbers. The Guardian states that 'Sound is vital for reef survival, because almost all of its inhabitants, from corals to crustaceans to fish, produce offspring that spend the early part of their lives in the open oceans, before us...

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...

22.11.2020 Animal of the week: Red foxes

Hello everyone, this week's post is about red foxes. Diet Foxes aren't fussy about what they eat. They will eat pretty much anything that they can get; rabbits, rodents, birds, frogs, earthworms, fruit, berries and a lot more. They also enjoy rummaging in food waste looking for scraps. Habitat and species Foxes normally live in forests but they are also found in mountains, grasslands and deserts. They live in burrows which they dig themselves. These provide safe places to store food and raise their young. They also are a nice cool place to sleep in. A burrow will have multiple exits in case a predator comes in. The most well known species of fox are the red fox and the artic fox. However there are many more types of fox that most people don't know about. Offspring Fox babies are known as pups. After mating, the female will make a nest out of leaves in the burrow. Foxes have litters of between two and seven pups. Looking...

How well do you know the Arctic and the Antarctic? - Quiz

Welcome back to Green World, As announced last week, we're starting our new monthly series: quizzes! This post contains the questions, you have to write down the answers and compare them with the solutions right at the bottom of this post. Questions: True or False? The Arctic is not actually a land mass, it's a frozen ocean. How many people live in the Arctic circle? a) 500 000 b) 4 million c) 10 million True or False? Narwals don't actually have unicorn-like horns. That's just a legend. What percentage of the world's freshwater is frozen within the Arctic's ice? a) 10% b) 15% c) 20% True or False? The Arctic covers parts of 15 different countries. Scientists exploring Antarctica have measured winds of up to... a) 100 km/h b) 150km/h c) 200km/h True or False? The driest (natural) place on Earth is in Antarctica...

New Year's Eve 2020 Challenge!!!

Challenge New Year's Eve is only a week away now. Hundreds of people set goals for the coming year on New Year's Eve. We would like you to set some goals that are about the environment. For instance cut down on how much meat you eat or use less plastic. You can chose the easy, the normal or the hard challenge. Easy Challenge For the easy challenge you only need to set one environmental goal. Normal Challenge To complete the normal challenge you will need to set three environmental goals. Hard Challenge This one is for people who are willing to give things up for the environment. To do the hard challenge you must set five environmental goals. Completion Date 31.12. (New Year's Eve) You have one week. Other info Tell us about your goals We would love you to tell us about your goals. If you wish to share them with us: just write them in a comment. Tips Don't set goals that you know you won't be able to complete. Just...

13.12.2020 Animal Of The Week: Lark

Hello, Today's post is all about a rather interesting bird I don't know much about and so I can't wait to discover more! Habitat There are many different species of Lark so they are quite widespread. Different websites say different figures but most agree that there are between 90 and 100 different species of Lark. They live in open countryside from deserts to mountains. Their colour is adapted to their environment and so they can vary in appearance. Diet Larks are omnivorous animals and eat many species of insects as well as seeds, leaves, grasses and fruits, especially in Winter as insects are scarce. Some species will also eat snails which they break open on rocks. Lark Song The lark is reputed for its song, especially when it is in flight. This is the reason that they are sometimes represented in poetry. I love poetry and I haven't read any Lark themed poetry yet but writing this has made me want to. However, the wi...

Animals 11-15 in our '50 incredible animals' series

Hello, We have another five amazing animals for you today. Enjoy! 11. Dhole This is a dog species which looks rather like a red fox . They are difficult to put into any of the dog subfamilies. They aren't foxes, nor wolves, nor domestic dogs. Dholes are fast runners and live in packs of 5-12 individuals. Although sometimes, different packs will join forces to become a pack of 30 or more individuals! However, these super packs are broken up after a successful hunt. The different packs rarely attack each other as neighbouring packs are often closely related. Dhole packs live in burrows with multiple entrances. They can be found in eastern and southern Asia. They eat wild berries, insects and lizards and as a pack hunt deer, rodents and other wild mammals. Interestingly, unlike other dogs, they rarely kill by biting at the throat. They are also good swimmers! 12. Irrawaddy dolphin The Irrawaddy dolphin can be found in coastal areas of south a...

Green World

Search This Blog