PLEA Network

30 September 2022, The Conversation, Shifting ocean currents are pushing more and more heat into the Southern Hemisphere’s cooler waters. The oceans absorb more than 90% of all extra heat trapped by the emissions we’ve produced by burning fossil fuels. This heat is enormous. It’s as if we exploded an atom bomb underwater, every second of every day.The ocean isn’t warming at the same rate everywhere. We know the heat is concentrated in the fast, narrow currents that flow along the east coasts of the world’s continents and funnel warm water from the tropics down towards the poles.In the Southern Hemisphere, these currents – known as the western boundary currents – are warming faster than the global average at their southern limits, creating ocean warming hotspots.Until now, we haven’t known exactly why. These western boundary currents are particularly important in the Southern Hemisphere, which is more than 80% ocean compared to just 60% for the Northern Hemisphere.Our new research has found a vital part of the puzzle: strong easterly winds in the mid-latitudes are moving south, driving the western boundary currents further south and leading to faster ocean warming in these areas. Read more here