Atmospheric

The global climate trend since Nov. 16, 1978 is +0.14 C per decade, according to scientists from the Earth System Science Center (ESSC) at The University of Alabama in Huntsville
April temperatures (preliminary)
Global composite temp.: +0.50 C (about 0.9 degrees Fahrenheit) above 20-year average for April.
Northern Hemisphere: +0.80 C (about 1.44 degrees Fahrenheit) above 20-year average for April.
Southern Hemisphere: +0.21 C (about 0.38 degrees Fahrenheit) above 20-year average for April.
Tropics: +0.63 C (about 1.34 degrees Fahrenheit) above 20-year average for April.
March temperatures (…

It is no secret that a majority of the peer-reviewed climate change literature lays blame for global warming on human greenhouse gas emissions.
But despite the abundance of research supporting anthropogenic global warming, there is a sizable community of qualified scientists who believe the so-called consensus view on global warming is completely wrong. I wanted to find out why, so I contacted one skeptical researcher to ask.
Dr. Roy Spencer is a climatologist at the University of Alabama in Huntsville. For many years he served as a Senior Scientist for Climate Studies at NASA’s Marshall…
Eyjafjallajoekull is erupting again and has sent another ash cloud, 1600 km wide, into the atmosphere. The brownish plume, traveling east and then south, is clearly visible in stark contrast to white clouds framing this Envisat image from 6 May.
The volcano began emitting steam and ash on 20 March, wreaking havoc on European aviation last month. Renewed activity earlier this week caused some flights to be suspended to and from Ireland, Northern Ireland and Scotland.
Authorities are monitoring the position and height of the ash cloud as well as the direction of prevailing Atlantic winds, which…

University of Sheffield geographers studying flowering plants say summers in England have been arriving earlier since the 1950s.
Researchers examined records of the first blooming date of early summer flowering plants (phenology) and the timing of first occurrences of warm 'summer' temperatures - events linked with the onset of summer.
Results revealed that the occurrence of 'summer' temperatures has advanced by 11 days in the 1990s compared to the period 1954-1963, while early summer flowering has advanced by three days. If this analysis is extended to 2007, the advance reaches 18 days.…

If human CO2 emissions continue unabated, the earth could become a difficult place to live before the end of the century, according to a new study in PNAS.
Researchers from Purdue University and the University of New South Wales, Australia calculated the highest tolerable "wet-bulb" temperature and found that this temperature could be exceeded for the first time in human history if future climate change scenarios are to be believed.
Wet-bulb temperature is equivalent to what is felt when wet skin is exposed to moving air. It includes temperature and atmospheric humidity and is measured by…

Plants are getting too much blame for global warming, according to a study by scientists at the University of Ediburgh and the National Center for Atmospheric Research.
The research, published in New Phytologist, suggests that plant leaves account for less than one per cent of the Earth's emissions of methane, considered to be about 25 times more potent than carbon dioxide. The results contrast with a previous scientific study which suggested that plants were responsible for producing large amounts of the greenhouse gas.
"Our results show that plant leaves do give rise to some methane, but…
Despite present-day conditions, Antarctica was not always covered with ice. Approximately 53 million years ago, the continent was a warm, sub-tropical environment and atmospheric CO2 levels exceeded today's by ten times.
But in just 400,000 years – a mere blink of an eye in geologic time – Antarctica's lush environment transitioned into its modern icy realm. Concentrations of atmospheric carbon dioxide decreased, global temperatures dropped, ice sheets developed and Antarctica became ice-bound.
How did this change happen so abruptly and how stable can we expect ice sheets to be in the…

University of Melbourne researchers writing in Nature say melting sea ice is a major cause of warming in the Arctic. The findings challenge previous theories which propose that warmer air transported from lower latitudes toward the pole, or changes in cloud cover, are the primary causes of enhanced Arctic warming.
Using the latest observational data from the European Center for Medium-Range Weather Forecasting, researchers were able to uncover a distinctive pattern of warming, highly consistent with the loss of sea ice.
"The sea ice acts like a shiny lid on the Arctic Ocean. When…

A new study in Nature Geoscience suggests that as global temperatures increase, microbes in soil become less efficient over time at converting carbon in soil into carbon dioxide, a key contributor to climate warming.
The results contradict those of earlier studies that assume microbes will continue to spew ever-increasing amounts of carbon dioxide into the atmosphere as the climate continues to warm. If microbial efficiency declines in a warmer world, carbon dioxide emissions will fall back to pre-warming levels, a pattern seen in field experiments. But if microbes manage to adapt to the…

Northwestern University scientists say Eyjafjallajökull and its massive cloud of volcanic ash have impacted mobility patterns in places far from Europe -- including the United States, India and southeast Asia.
The team compared the entire worldwide air transportation network before and after the 27 major European airports were closed and used complex network theory to compute and list the most affected airports still operating.
"We were surprised to discover that at the top of the list were airports outside of Europe, not airports in Europe," Northwestern University professor Dirk Brockmann…