Wayne Stollings wrote:
That is one of the concerns over climate change, that the pattern will change enough that crops are impacted and production is lowered.
I actually think that there is little doubt that weather patterns have
already changed.
In southern Australia, high pressure systems now pass to the south of the continent during summer, whereas some 30 years ago the high pressure systems tracked along the southern coastline. The difference in tracks is in the order of a 150 miles or more further south. In winter the highs are now closer to the southern wheat belts which in turn reduces the likelihood of rain bearing cold fronts providing adequate rainfall for the crops.
I understand that the situation is similar in the northern hemisphere.
http://www.sciencedaily.com/releases/2005/09/050922015634.htmQuote:
Previous research has shown that over the past thirty years air pressure trends have contributed about 1°C to warming over the UK in winter and up to 3°C in Siberia, as well as 60% of the rainfall increase seen in Scotland.
on a related issue I notice that over the last few months there has been a succession of weather related disasters.
here is quick list off the top of my head
The Sandy hurricane
The Philippines typhoon
The Samoan / Fiji cyclone
Floods in the UK
Tornadoes and heavy snowfall in the USA over the last few days
For a more detailed list try here and change the month as required
http://www.ncdc.noaa.gov/sotc/hazards/2012/11