Local Sea Level Rise- one of the trickiest predictions, part 3: Trade Winds and Atmospheric Pressure
Local Sea Level Rise- one of the trickiest predictions, part 3: Trade Winds and Atmospheric Pressure.We have covered in the previous posts (http://on.fb.me/1C2B9Lx and http://on.fb.me/1JsFhdw ) how sea level change will be felt differently throughout the world. You may be starting to see how complex the sea level rise predictions are! But, it gets even more complex. In this post we will explain how trade winds and atmospheric pressure can influence local sea level rise.Winds have the ability to push masses of water in a certain direction. Regional sea level variations can be associated with changes in prevailing winds and the resulting changes in ocean circulation. An example of this situation has been observed; between the years of 1993-2010 there was a large sea level rise in the western tropical Pacific and a sea level fall in the eastern Pacific. This was due to an increase in the intensity of the trade winds in the central and eastern tropical Pacific in the same time period.Regional sea level also changes when the atmospheric pressure changes. If air pressure increases over a region of water, it will be ‘pushed’ toward another region (it’s a bit like blowing on some water- you can see the ripples moving away from where you are blowing). It is predicted that sea level pressure will increase over the subtropics and mid latitudes (decreasing sea level) and will decrease over higher latitudes (raising sea level). The decrease in sea level pressure is projected to be most extreme in the Arctic, in the order of several millibars, which is especially concerning as lower air pressure is usually associated with warmer temperatures – a big problem for our Polar Bears.-MJAReferences/Further reading:IPCC on sea level rise: http://bit.ly/1CrvtOkImage Credit: Florian Schulz -- source link
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