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The Heat is On!

Photograph: Joe Raedle/Getty Images


The Heat is On! 

How Warming Oceans are Changing Our World

You're taking a dip in the ocean on a sunny day. You expect the water to be refreshing and cool, but instead it feels warm and cozy. You might think you're lucky to find such a pleasant spot, but what you're actually experiencing is a sign of a troubling trend: ocean warming.

Ocean warming is the increase in the temperature of the world's oceans due to human-caused climate change. It's not a new phenomenon, but it's accelerating at an alarming rate. According to NASA, the ocean has absorbed 90% of the warming that has occurred in recent decades due to increasing greenhouse gasses, and the top few meters of the ocean store as much heat as Earth's entire atmosphere.

Why does this matter? Well, for starters, ocean warming affects sea level rise, coral bleaching, ice sheet melting, hurricane intensity, and ocean health and biochemistry. Let's take a closer look at some of these impacts.

  • Sea level rise: As water heats up, it expands and takes up more space. This is called thermal expansion, and it's responsible for one-third to one-half of global sea level rise. Sea level rise threatens coastal communities and ecosystems with flooding, erosion, saltwater intrusion, and habitat loss.

  • Coral bleaching: Corals are animals that live in symbiosis with algae that provide them with food and color. When the water gets too warm, corals expel their algae and turn white, a process known as bleaching. Bleached corals are stressed and more vulnerable to disease and death. Coral reefs are home to a quarter of all marine life and provide many benefits to humans, such as tourism, fisheries, and coastal protection.

  • Ice sheet melting: The oceans are not only warming at the surface, but also at depth. This means that warm water can reach the edges of ice sheets in Greenland and Antarctica and melt them from below. Ice sheet melting contributes to sea level rise and also alters ocean currents and salinity.

  • Hurricane intensity: Hurricanes are fueled by warm ocean water. As the oceans get warmer, hurricanes can grow more powerful and produce more rainfall. For example, Hurricane Idalia, which hit Florida this year, was likely intensified by 40-50% due to hotter ocean temperatures from global warming.

  • Ocean health and biochemistry: Ocean warming affects the physical and chemical properties of seawater, such as its density, circulation, oxygen level, pH, and nutrient availability. These changes can have cascading effects on marine life, such as altering their distribution, migration, reproduction, growth, and survival. Ocean warming can also trigger harmful algal blooms, fish kills, and marine heat waves.
As you can see, ocean warming is a serious issue that affects not only marine life, but also human life and well-being. But what can we do about it? The main cause of ocean warming is the excess greenhouse gasses in the atmosphere that trap heat from the sun. Therefore, the most effective solution is to reduce our greenhouse gas emissions by switching to renewable energy sources, improving energy efficiency, and adopting low-carbon lifestyles. We can also help by supporting ocean conservation efforts, such as creating marine protected areas, restoring coastal habitats, and reducing pollution and overfishing.

As the waters of our oceans continue to warm, the clock is ticking. The time to act is now. Together, we can make a difference and protect our precious oceans for generations to come!

Check out this website for a study by Cal Poly on marine heatwaves and cold spells!