A R C T I C I N T E G R A T E D E C O S Y S T E M R E S E A R C H P R O G R A M
Here, we report some of the major findings of our research. Background information and an outline of next steps follow.
The Chukchi Sea is warming Water temperatures in July to October in recent years were nearly 3 ºC (5 ºF) warmer than the average temperature for these same months in the early 1970s. Water from the Bering Sea flows northward into the Chukchi and Beaufort Seas. Ocean currents from the North Pacific have recently carried extra heat onto the Bering Sea continental shelf each year, reducing local sea ice extent and duration. Early ice retreat causes the ocean to absorb extra sunlight energy in the spring, leading to a warmer- than-normal ocean in summer and fall. Increasing northward flow at Bering Strait is mirrored by an increase of flow northward through Barrow Canyon into the Beaufort Sea. At least 50% more heat is subsequently available for melting ice and warming the waters of the Arctic Ocean. For example, there is enough excess heat exiting the Chukchi Sea through Barrow Canyon to warm the upper 100 m (300 ft) of the entire Beaufort Sea by roughly 0.5 °C (0.9°F).
Warming oceans are warming the Arctic atmosphere As Chukchi Sea waters have warmed, more heat is now released back to the atmosphere in autumn (about 30% more), making the Chukchi Sea an important contributor to warming Arctic air temperatures. Warming waters inhibit sea ice growth In fall, the excess heat gained by the ocean over the spring and summer must be lost back to the atmosphere before sea ice can form. Warmer waters in recent years have delayed fall ice growth by many weeks. South winds during winter contribute to early spring ice retreat Increasingly, winds are blowing from the south during winter, driving the sea ice and warm ocean water northward and contributing to early spring ice retreat.
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