A picture is worth a thousand words:
It isn’t global.
This is weather, not climate. It is caused by a persistent blocking high pressure pattern. In a day or two, that red splotch over the eastern USA will be gone.
Image from Dr. Ryan N. Maue of WeatherBELL
h/t to Joe Bastardi
UPDATE: Dr. Roy Spencer puts it in perspective
July 6th, 2012
I know that many journalists who lived through the recent heat wave in the East think the event somehow validates global warming theory, but I’m sorry: It’s summer. Heat waves happen. Sure, many high temperature records were broken, but records are always being broken.
And the strong thunderstorms that caused widespread power outages? Ditto.
Regarding the “thousands” of broken records, there are not that many high-quality weather observing stations that (1) operated since the record warm years in the 1930s, and (2) have not been influenced by urban heat island effects, so it’s not at all obvious that the heat wave was unprecedented. Even if it was the worst in the last century for the Eastern U.S. (before which we can’t really say anything), there is no way to know if it was mostly human-caused or natural, anyway.
“But, Roy, the heat wave is consistent with climate model predictions!”. Yeah, well, it’s also consistent with natural weather variability. So, take your pick.
For the whole U.S. in June, average temperatures were not that remarkable. Here are the last 40 years from my population-adjusted surface temperature dataset, and NOAA’s USHCN (v2) dataset (both based upon 5 deg lat/lon grid averages; click for large version):
Certainly the U.S drought conditions cannot compare to the 1930s.
I really tire of the media frenzy which occurs when disaster strikes…I’ve stopped answering media inquiries. Mother Nature is dangerous, folks. And with the internet and cell phones, now every time there is a severe weather event, everyone in the world knows about it within the hour. In the 1800s, it might be months before one part of the country found out about disaster in another part of the country. Sheesh.