Not exact matches
Countless additional forces — melting ice sheets, shifts
in precipitation,
changes in atmospheric and oceanic
circulation, to name a few — will
influence the process as well.
As discussed
in the Climate chapter, large - scale
atmospheric circulation patterns connected to
changes in sea - surface temperatures strongly
influence natural variations
in precipitation and temperature (e.g., Cayan et al. 1999; Mantua and Hare 2002).
Yet, we explained there is also reasonable basis for concern that a warming world may at least temporarily increase tornado damage including the fact that oceans are now warmer, and regional ocean
circulation cycles such as La Nina / El Nino patterns
in the Pacific which affect upper
atmospheric conditions appear to becoming more chaotic under the
influence of climate
change.
The main modulating
influence on tropical cyclone activity
in the western North Pacific appears to be the
changes in atmospheric circulation associated with ENSO, rather than local SSTs (Liu and Chan, 2003; Chan and Liu, 2004).
The large interannual to decadal hydroclimatic variability
in winter precipitation is highly
influenced by sea surface temperature (SST) anomalies
in the tropical Pacific Ocean and associated
changes in large - scale
atmospheric circulation patterns [16].
One last point related to my last post, is the extent / degree of magnitude of a more meridional
atmospheric circulation pattern (N.H. especially) could
influence snow cover, cloud cover, and precipitation amounts which could set up stronger positive climatic feedbacks, which could then result
in an even more significant climatic
change going forward.
These aspects of precipitation generally exhibit large natural variability, and El Niño and
changes in atmospheric circulation patterns such as the North Atlantic Oscillation have a substantial
influence.
The current California drought is bad because for the first time ever, scientists from many different fields see parallel lines of evidence for the
influence of human - induced climate
changes, including the fingerprints of higher temperatures and
changes in the
atmospheric circulation patterns.
I think it is really important to make that distinction - that there are a number of factors that
influence the extent of Arctic sea ice, some of them of course associated with
changes in the radiative forcing from the atmosphere, as a result of anthropogenic greenhouse gases and aerosols, but also
changes in the
atmospheric circulation and also the advection of heat into or out of the Arctic by the ocean
circulation.
Their
influence on the
atmospheric circulation is focused on the polar regions by the Earth's magnetic field [the opposite phase of the
changes in the Arctic and the Antarctic can be explained by the phenomenon of «solar system dissymmetry» as a result of which fluctuations of solar constant occur].
Other proposed mechanisms confine the Arctic's
influence on large - scale
circulation changes to the troposphere,
in which a warmer Arctic favors a wavier flow and more persistent
atmospheric blocking, which often spawns extreme weather events58, 59.