Nicholas Tyrrell edited From_one_year_to_the__.tex  over 8 years ago

Commit id: 18cde59289c9e292542a85445d053b20f5eac8aa

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is being amplified over the land. Interesting! But lets pull it apart a bit   more.   We know that the \href{http://www.bom.gov.au/climate/enso/}{El Ni{\~n}o-Southern   Oscillation} is the main source of year to year temperature variability in the   oceans. It occurs in the tropical Pacific but is strong enough to have a global   influence.\\   We can take our climate model again but instead of assigning the   whole ocean temperature we just put in a "fake" El-Ni{\~n}o/La-Ni{\~n}a.   We make the tropical Pacific ocean temperatures go up and down - over   a period of four years - and let the rest of the ocean, and the land, respond.\\   In this experiment, the global land surface temperature still   responds with amplified variability relative to the ocean, so if the ocean surface temperature increases or decreases by $1^{\circ}$ the land temperature will increase or decrease by almost $1.5^{\circ}$. Essentially, we can   control the global land temperature by changing the temperature of the tropical   Pacific ocean. \\  You might ask; what if you changed the temperature of the Southern Ocean or the   North Atlantic, would you get the same land response?\\   The answer is, no.\\   We've found that the tropical oceans have the greatest influence on land temperatures. The reason is   that warmer tropical oceans result in lots of atmospheric convection from the   surface up to about 10-15km above the ocean: the troposphere. Changes in colder   ocean temperatures will not cause the kind of convection that penetrates up into   the troposphere.\\   If you add what we call a temperature perturbation to the troposphere, the tropical atmosphere will efficiently transport that perturbation around the globe, so for a big enough perturbation the Once the warmer temperatures reach the troposphere, they spread   out and encircle the earth. The ocean temperature changes are amplified because   the land is more responsive to these tropospheric temperature changes.  What does this mean for us?\\   Right now, in the Pacific ocean, there is a very   large El Ni{\~n}o brewing. It has the potential to be one of the largest on   record and will probably keep getting warmer until December or January. This   means that we expect the global land surface to have an amplified response to   the ocean temperatures and 2015 and 2016 to be very warm years!