[Global average lower tropospheric temperature
(LT) anomaly for May, 2014 is +0.33 deg. C, up from April.
An El Niņo (Spanish for The Child, because it was
first observed by Peruvian fishermen around Christmas) is a shift in the
temperature patterns of the Pacific, as a blister of equatorial ocean heat moves
eastwards. It is a natural cyclic event that tends to reverse the prevailing
Pacific weather patterns, often damagingly, and is not connected with climate
change − although its effects could be made worse by climate change.
“The long-term baseline temperature is about three
tenths of a degree warmer than it was when the big El Niņo of 1997-1998 began,
and that event set the one month record,” Christy said. “With the baseline so
much warmer, this upcoming El Niņo won’t have very far to go to break that
0.66°C record. That isn’t to say it will, but even an average-sized warming
event will have a chance to get close to that level.”
Meanwhile, according to new research in Nature
Climate Change, people in the northern hemisphere can also expect warmer
temperatures in autumn and winter – in spite of last winter’s spectacular ice
storms in the US north-east that shut down cities from the Atlantic to the
Midwest, and where − to the joy of headline writers − the town of Hell in
Michigan froze over.
Extremes of cold
The report's author, James Screen, Natural
Environment Research Council research fellow at the University of Exeter, UK,
says that even though there will be extremes of cold, these will be less
frequent and less severe. The Arctic is warming, and a study of autumn and
winter temperature variations shows that variability in the temperate zone
overall has in fact decreased.
“Autumn and winter days are becoming warmer on
average, and less variable from day to day,” Dr Screen said. “Both factors
reduce the chance of extremely cold days.
“Cold days tend to occur when the wind is blowing
from the north, bringing Arctic air south into the mid-latitudes. Because the
Arctic air is warming so rapidly, these cold days are now less cold than they
were in the past.”
Source: Climate News Network