A new study published in the journal “Geophysical Research Letters” shows that global warming is changing wind-driven ocean currents.
Changing the ocean circulation is a big deal. It can effect food supplies, fisheries, the sea level and weather in densely populated coastal areas.
Climate change is moving major wind-driven ocean currents toward the poles at the rate of a mile every two years. This eliminates nutrients from coastal fishing areas and causes sea level rise, extreme storms and heatwaves.
This is bad news for the East Coast of the US.
At 40 degrees latitude north, where these new currents are most evident along the East Coast, sea level rise is already 8 to 12 inches more than in other areas.
This shift in currents is causing problems on the US west coast as well. Here salmon are being pushed out of traditional fishing waters.
“In densely populated coastal Asia, the changes could unleash more intense rainstorms, and the shift also makes heat waves more likely in subtropical areas.”
Wind-driven ocean currents are known as gyres. There are eight of these gyres which circulate in vast areas of the ocean. These rotating currents shape the weather and ocean ecosystems in coastal regions.
The Gulf Stream along the US east coast is a gyre.
And now climate change is shifting the major ocean gyres. This has been seen in more than 40 years of satellite measurements.
Some of these shifting gyres are now moving warmth and moisture from the tropics to higher latitudes.
The lead author of the study Hu Yang, says that as waters get warmer, the cold water fish really don’t have any place to go. The North Pacific is blocked by continents. The result is that fish die and fisheries decline.
This is also happening in the South Atlantic.
“A fisheries decline in the South Atlantic off the coast of Argentina documented as long as 10 years ago may also be linked with the southward shift of one of the gyres.”
“Ocean currents also distribute the eggs and larvae of marine organisms over wide areas, so the shift of the gyres is likely to affect the distribution of many species.”
This is happening all over the world.
On the east coast of the US, the Gulf Stream has shifted northward and this has chased the Cod out of the gulf of Maine.
The changed coastal currents are also moving pushing more intense storms toward the coast of Asia.
And Yang says that there was no reason to think that all of these changes will slow down or stop anytime soon.
He said that “As long as the global temperature keeps increasing, this movement of the currents cannot really stop, because the climate is not in equilibrium with CO2 levels. In our lifetime, I don’t think it will stop,” he said.
In large and small ways, global warming is changing our world. And many of these changes are not beneficial to humans.
More reading on this subject
Summary: Warming is changing ocean currents. A new study published in the journal “Geophysical Research Letters” shows that global warming is changing wind-driven ocean currents. Changing the ocean circulation is a big deal. It can effect food supplies, fisheries, the sea level and weather in densely populated coastal areas.