Climate Action
Holy Ship! 11 Absolutely Bonkers Ocean Facts
June 13, 2025
Today we’re taking a dive into some of the truly crazy things going on in our oceans right now due to climate change. Despite making up roughly 70% of Earth’s surface, we know way less about what is happening beneath the waveline that we do above it but here are some of the crazier things researchers are just discovering.
1. Not Clowning Around: Small but Mighty
A recent study found that clown fish are shrinking – literally. Nestled into the coral reefs of Papua New Guinea, clownfish are typically only 3 inches in length anyway but scientists observed that they shrink their bodies by 1-2% in response to heat stress. This has improved their chances of surviving by a staggering 78%. No wonder they couldn’t find Nemo!
2. Caspian Sea is Shrinking
It’s not just clownfish shrinking due to warming oceans – the Caspian Sea is slowly disappearing as rising temperatures increase evaporation. As an inland body of water, the lack of rain and river discharge worsens the issue. As a stark contrast to globally rising sea levels, scientists anticipate a rapid decrease in the Caspian’s sea’s water levels. In fact, its average rate of decline from 2020-2023 was 23.3 centimeters per year.
3. A Major Supply of Minerals
Did you know that oceans contain 37 out of 50 minerals that the U.S. relies on for feeding crucial supply chains and national as well as economic security? Unfortunately, essential minerals like manganese, cobalt, and platinum are found deep beneath the sea, meaning deep-sea mining is threatening fragile ecosystems.
With the exact impact on biodiversity still so uncertain, scientists, governments, conservation organizations, and citizens alike are urging companies to pull back the pickaxe and deep sea dredgers. In February 2025, the European Union (EU) Parliament voted against Norway’s decision to go ahead with deep-sea mining in the Arctic and instead reaffirmed its moratorium position. It called for the European Commission and member states to back an international moratorium on deep-sea mining.Let’s hope that gets traction, and soon.
4. Heart of the Sea
Like the human regulatory system, ocean currents provide essential heat and moisture circulation worldwide. One such process, El Niño Southern Oscillation (ENSO), increases sea surface temperature in the Pacific Ocean. But recent studies suggest global heating is strengthening El Niño, and occurrences may increase over the next century. This potential positive feedback loop is sure to make Earth’s and our hearts race.
The consequence will amplify global climate instability, leading to more yet extreme weather, more disrupted ecosystems, and greater threats to food, water, and human security.
5. Enough Salt for the Table?
Apart from record-breaking heat in 2023, El Niño also alters the chemistry of coastal waters. Scientists found that the salinity, an important indicator in the water cycle, is up to 30 times more variable along coasts than the open ocean. Researcher’s anticipate the stronger ENSOs (due to climate change) will heavily impact marine life along our coastlines especially.
6. Slower Sperm – UV Got to Be Kidding Me
Bleaching and thermal stress pose major threats to coral reproduction, which is vital for maintaining healthy underwater ecosystems. In Montipora capitata, a Hawaiian rice coral, bleaching has been linked to a decline in coral polyp sperm motility—from a healthy 70-90% down to around 40%.
Fortunately, another species, Montipora spp. (Hawaiian blue rice coral), produces a protein that acts like sunscreen. By filtering out UV radiation, this protein appears to help mitigate the damage that other rice corals are suffering from.
7. It Actually Is That Deep
The Challenger Deep, is the deepest known part of the ocean and located in the Mariana Trench. But despite depths of about 36,200 feet, and air pressure 1,100 times higher than what our bodies normally experience, a plastic bag still found its way all the way down there.
Plastic trash is nobody’s treasure, with 89% of the plastic scientists recorded in a 30-year debris blog being specifically single-use plastic. Probably used once for mere minutes and then thrown away to go to an imaginary plastic recycling plant – which means dumped in the ocean!
8. It’s Getting Hot in Here
Did you know that almost 60% of the world’s ocean surface experienced a heatwave in 2021? Our amazing oceans absorbed 90% of that excess heat caused from global warming, but marine heatwaves are causing wide scale reef degradation and coral bleaching.
The UN Environment Programme has warned that every single coral reef could bleach by the end of this century. To combat this pandemic of coral bleaching we need a range of actions – we must reduce our carbon emissions so we can use renewable energy instead. We need to improve water quality, strengthen existing marine protected areas and create many more and we must back sustainable fisheries.
9. When A Green Thumb Is Bad
Columbus may have sailed the ocean blue, but over the past 20 years scientists have found that the tropics are getting greener. Climate change is increasing the number of phytoplankton,the microscopic, plant-like organisms that form the foundation of the ocean’s food web.
Unfortunately, overaccumulation of these organisms may lead to toxic algal blooms and this may lead to virus infected phytoplankton releasing toxins. These algal blooms, paired with unsustainable farming practices, can lead to instances like the 2014 Toledo Water Crisis.
Which saw 500,000 residents in Toledo, Ohio, advised not to drink or even use their tap water for days due to contamination from a harmful algal bloom in Lake Erie.
10. The Twilight Zone
Although not quite an otherworldly dimension, the ocean’s mesopelagic region, or Twilight Zone, extends from 200 down to 1000 metres deep. It could contain about 100 times the amount of fish as fisheries catch in a year. Including vampire squid, bristlemouths, giant squid, deep-sea anglerfish, and stunning bioluminescent jellyfish. Most of its inhabitants have yet to be discovered and named.
Unfortunately, with no global government protection framework in place for this area of the world’s oceans, this mysterious region’s creatures may be lost to us before we even discover what they are.
11. A Little OverKrill
Apart from being the largest animals on Earth, blue whales consume a staggering 40 million krill, small shrimp-like crustaceans, a day! That’s roughly the equivalent, if we let one krill equals one person, of the population of Canada.
But with the rapid melting of polar ice due to climate change, the algae plankton that typically grow in the underside of sea ice lose their habitat. These algae are a crucial food source for krill, so once the ice plankton is gone the krill too – limiting the food supply for beautiful blue whales.
Whale, You Can Help
Unfortunately, like many of our ocean friends, blue whales are classified as an endangered species. Other whales in need are two very specific orcas, mom Wikie and her son Keijo – trapped in a closed Marine park in Antibes, France. Our article Lost in Limbo: Saving Wikie and Keijo shares the mother-son orca’s plight.
With the UN 2025 Oceans Conference starting in Nice on June 9th, just 22 km’s from Wikie and Keijo, if you care we urge you to take minutes to help them by writing a letter to French President Emmanual Macron – to demand his intervention. He must ensure these animals are cared for to the highest possible standards and not left to suffer or even die in a theme park.
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