Fair use for educational and discussion purpose:

False springs, where uncharacteristically early warm weather is followed by a sudden hard freeze, can have a devastating effect on vegetation and agricultural crops by killing off early growth. Now researchers from Oak Ridge National Laboratory, US, who analysed more than 100 years of data to look for a trend in the frequency of false springs over the southeastern US, have found considerable regional variations.

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Fair use for educational and discussion purpose:

Relax farmers: climate change is good for you (not)

A recent New York Times article reported how ag scientists around the world are beginning to note how many of the failed harvests of the past decade have been the result of weather disasters—floods, drought, unprecedented heat waves.

Many of these scientists are now admitting that global climate change will probably have a net negative effect on agriculture. That’s a tough one to swallow for some, since so many in the scientific community spent the 1990′s and 2000′s telling us that carbon dioxide (the main contributor to climate change) would boost plant growth so much that it would offset any other negative effects caused by an altered climate.