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

November Top Tips | sustainable activities and hobbies

Hello everyone, So this week, we are going to be talking about sustainable free time activities. This area can quite big when it comes to environmental impact, so here are some things that you can do in your free time, that are more sustainable. 1. Reading So reading is one of our favourite things to do. However, books are made of paper and the paper industry isn't great. Some ways you can get around this is by reading online (for example, on a kindle), or through borrowing books from a library or using book boxes. If there aren't any in your area then at least try to support independent bookshops! 2. Running If you love being active then this one is for you. Running is probably one of the most sustainable forms of sport. All you need are some running shoes and somewhere to run. There is obviously more high-tech gear but that isn't really necessary if it's just a hobby. 3. Gardening If you've got a small area of land o...

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...

Ecosia

We all need to do something to save our planet: it is no use just leaving it to Greta Thunberg! She is very inspirational, yes, but she can only do so much. She isn't superhuman! The climate crisis is up to us; up to you. We all have to get stuck in. Research, learn, discover and most importantly: never give up! The world's animals need us. The world's trees need us and a simple way to do this is to switch to Ecosia. Ecosia is a search engine but it plants trees while you search the web. Okay, it doesn't have as many websites as google so you may want to have google as a backup but it plants trees: this is your opportunity to make a simple change. Just google Ecosia and search to plant trees. Make a difference. Image: This image is owned by Binyamin Mellish on pexels.com .

Energy comparison: coal the pros and cons

Hello, Today we're talking about coal and how it's used as an energy source. As you've probably already noticed we're not really big fans of coal. So this post is going to be looking into the pros and cons of coal as an energy source. General facts Coal is a black sedimentary rock, made of carbon and hydrocarbons, that is found underground. It is formed by the remains of prehistoric plants and animals being buried deep in the earth under the right pressure. Coal, therefore, takes millions of years to form. Pros There are quite a few pros to using coal as an energy source. Firstly, it's cheap with a low cost per energy unit. It is also reliable as it can be burned at all times of day, during any weather and at any time of year. This is a big advantage because a lot of renewables are weather-dependent ( solar , wind , ...). There is also currently an abundance of coal, enough to last a few hundred years. It is also e...

January Top Tips // 5 ways you can individually tackle climate change

Hi Everyone! This is the first of our new monthly posts for 2022! We will be sharing top tips every month, near the beginning, for things you can do during that month for the better. It's almost like a whole year of new year's resolutions (though let's hope they are achieved)! In these posts, we aren't just going to talk about climate change , of course, there will also be posts about animals , plants, habitats, plastic pollution and so much more! They will not be huge tips though, they won't demand too much of you (usually!). We need rebellions and people in the public eye spreading the word of course but we also need people like you, who can just do their bit. So, welcome to our top tips posts! We all know that we need to come together to fight the climate crisis, but we don't seem to be doing that right now. So here are our top tips for ways you can individually tackle climate change, even if this means simply spreading ...

Rachel Carson 1907-1964

Hi everybody, Today I am going to tell you about a really inspirational environmentalist. Her name is Rachel Carson. I hope her story inspires you to be more careful about pesticides. As a girl, Rachel adored writing stories about animals. She got a degree in zoology but had to go home to care for her ageing mother. She wrote a series of radio shows about fish for a living. Rachel's program, called 'Romance Under Waters', was a big hit. Her ways of writing were different to anyone else and no one had made that sound so interesting before. It proved that she was talented in not only science but also writing. She wrote two books called 'The Sea Around Us' and 'The Edge Of The Sea'. When Rachel moved to the countryside, she realized the impact of pesticides. At that time farmers sprayed chemicals on their fields a lot to protect them from animals that may want to eat them. Rachel worked out that they were killing pla...

19.07.2020: Animal of the week: Honey Bees

Hi everyone, This week's animal is the honey bee. Enjoy! General Information An average honeybee hive is made up of one queen, hundreds of male drones and thousands of female workers. If the queen bee dies then a new queen is created. The workers select a young larva and feed it with a special food called ‘royal jelly’. The ‘royal jelly’ makes the larva grow into a fertile queen. Queens live for several years but the workers only live for five or six weeks. An average worker will make a twelfth of a tee spoon of honey during her entire life. Drones are turned out of the hive and left to die in Autumn. In the summer months, the queen bee is very busy, she can lay up to 2500 eggs in a single day. How they affect the world around them Honey bees are very important for flowers, fruit and vegetables. This comes from the fact that they are pollinators. They help the plants by transferring pollen between male and female parts, meaning the plants can g...

The life of ... a cicada

Hi everyone, We're back to talk about another animal. Cicadas ( Cicadoidea ) are invertebrates and are 1.9cm to 5.7cm in size. There are 3 000 species that can be divided into annual cicadas and periodical cicadas. Annual cicadas can be seen annually and are found worldwide whereas periodical cicadas only leave the ground every decade or two and are only found in North America with hotspots in the eastern and central areas of the United States. Most annual cicadas have a lifespan of about two to five years and periodical cicadas can live up to the age of 17. Female cicadas lay around 400 eggs split up over several places. They normally lay their eggs on twigs, branches or other vegetation. The eggs hatch after about six to ten weeks, now known as nymphs, and dig their way into the soil. The nymphs feed on the liquids found in plant roots. They fully develop underground, before molting their shells and coming to the surface, now fully deve...

March Top Tips // 10 little things you can avoid in daily life

Welcome to the Top Tips this month! We'll be talking about 10 things you can avoid using in everyday life. We know it's a really simple topic, but it can actually make quite a difference. The avoidable stuff will be things many use because they look nice or taste nice or similar, but aren't actually necessary. We will also write a couple of facts on these things, and give ideas on how you could substitute them if possible. Many might be very obvious, but think about it, do you actually not use them? Have fun! Chewing Gum Most people would not be surprised when told that lots of chewing gum have synthetic colouring and flavouring. However, most people would be surprised when told that chewing gum is largely made of plastic. What the companies call the "gum base" is plastic and partly made of the same stuff plastic bags are made of. The gum contains microplastics that, if you spit your gum on the ground often tend to get into the oce...

02.08.2020 Animal of the week: Owl

Hi everyone, This week's blog post is all about owls. Habitat There are many different types of owl: barn owls, long-eared owls, snowy owls and lots more. Different species live in different places. Here are a few examples. Snowy owls live in the Arctic . Great grey owls live in pine forests. Elf owls live in deserts. There are about 130 different species of owl. Owls can be found everywhere in the world apart from Antarctica . Owls live in trees, holes in the ground, barns and caves. Most owls do not migrate in winter. Diet Owls eat insects, spiders, fish, reptiles, amphibians, birds and small mammals. What they eat the most depends on the type of owl and where it lives. Screech owls feed mostly on insects. Barn owls mainly eat mice, shrews and voles. Eagle owls eat hares and young foxes. Some owls can even fish like the Asian Fish Owl. Even though some species prefer a certain type of food, most owls will eat whatever they can find...

Green World

Search This Blog