Posts Tagged ‘North Atlantic’

Global average temperature has increased over the last 150 years, leading to widespread ice melt and rising global average sea level. The increase has not been at a constant rate – the Intergovernmental Panel on Climate Change identified two periods of accelerated warming, 1910 to 1945 and 1976 to 2000.

The earlier warming is poorly understood. Climate scientists disagree over causes suggesting solar activity, volcanic eruptions, and manmade emissions. The later warming has been attributed to anthropogenic causes, though scientists disagree over the proportion contributed by internal variability.

I am studying the earlier warming in the North Atlantic. Analysing historical observations I have found atmospheric circulation changes may be a key mechanism behind the warming. Using climate models I can test which processes could have been involved. Climate models are numerical representations of the climate system. They allow specific processes to be studied and can provide data where observations are not available, such as 3D ocean properties. Initial investigations have found large changes in ocean heat transport at the time of the warming.

Understanding the roles of atmospheric circulation and ocean heat transport will help us separate mankind’s influence on climate from natural processes, allowing better estimations of future climate change.


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