Atmospheric

Plants help keep us cool by absorbing CO2 - sometimes too cool.  The arrival of the first plants 470 million years ago triggered a series of ice ages, according to a research team that set out to identify the effects that the first land plants had on the climate during the Ordovician Period, which ended 444 million years ago. During this period the climate gradually cooled, leading to a series of 'ice ages'. This global cooling was caused by a dramatic reduction in atmospheric carbon, which this research now suggests was triggered by the arrival of plants. Among the first plants to grow…

Okay, not despair. But frustration. This is my fourth year in this PhD program, and it's getting to be crunch time. Everything that influences and directs my degree program are pushing me formore work, more specialization, and less of everything else. The project I'm working on is so specific that there are probably only 3 or 4 people that would completely understand why I'm doing it. I'll try to explain the specifics, and their pros and cons and I perceive them. I fully understand that a doctoral degree requires specialization so that I can publish something original. By and far, original…

Do we really care about climate change? Since we do very little to reduce or limit activities that we believe we know cause climate change one could argue that we - do - not - in - fact - care. Come again?! I can almost hear you say. At a AGU Town Hall meeting in San Francisco last night a group of engaged scientists discussed "Directions in Climate Change Education and Communication" In the AGU program this meeting was introduced the following way: The compelling nature of anthropogenic climate change is well documented in science literature. But the public and educators clearly lack…

Researchers using the Ozone Monitoring Instrument (OMI) on NASA's Aura satellite have confirmed major reductions in the levels of sulfur dioxide, a key pollutant generated by coal power plants which contributes to the formation of acid rain, in the eastern United States.  The analysis, the first satellite observations of this type, showed that sulfur dioxide levels in the vicinity of major coal power plants have fallen by nearly half since 2005, which confirms ground-based measurements of declining sulfur dioxide levels and demonstrate that scientists can potentially measure levels of…

The climate change effect of CO2 released from peat may be far greater than assumed. Drought causes peat to release far more carbon dioxide into the atmosphere than has previously been realized, according to new research. Much of the world's peatlands lie in regions that are predicted to experience increased frequency and severity of drought as a result of climate change, leading to the peat drying out and releasing vast stores of carbon dioxide (CO2) into the atmosphere. It's the very wetness of the peat that has kept the air out, locking in centuries of carbon dioxide that would normally…

New research in Nature has a surprising conclusion; the impact of deforestation on global warming varies with latitude, which at least explains a frustrating lack of warming in the U.S. even though global warming has been measured higher overall. The researchers calculated that north of Minnesota, or above 45 degrees latitude, deforestation was associated with an average temperature decrease of 1.5 degrees Fahrenheit. On the other hand, deforestation south of North Carolina, or below 35 degrees latitude, appeared to cause warming. Statistically insignificant cooling occurred between these two…

During the last decade, the almost singular focus on CO2 has been something of a puzzle; leaving out methane, with 23X the warming impact of CO2, seemed like a mistake. The ancient past tells us why methane should not be underestimated.  One hypothesis about the Paleocene-Eocene Thermal Maximum (PETM) is that the release of massive amounts of carbon from methane hydrate frozen under the sea floor 56 million years ago caused the greatest change in global climate since a dinosaur-killing asteroid presumably hit Earth 9 million years earlier, has gotten some new validation. …

Estimates show that 2010 was by far a record year for CO2 emissions from fossil-fuel combustion and cement manufacture. Globally 9,139 Teragrams, a teragram is a million metric tons, of oxidized carbon (Tg-C) were emitted from these sources. Converted to carbon dioxide, so as to include the mass of the oxygen molecules, this amounts to over 33.5 billion metric tons of carbon dioxide. The increase alone is about 512 Tg-C, or 5.9%, over the 2009 global estimate. The previous record year was 2008, with 8,749 Tg-C emitted; the 2010 estimate is about 104.5% of that, or 391 Tg-C more. Much of the…

Prevailing wind shear patterns prohibit cyclones in the Arabian Sea from becoming major storms but a new study says winds are weakening and that has enabled the formation of stronger cyclones in recent years -- including storms in 2007 and 2010 that were the first recorded storms to enter the Gulf of Oman. The researchers writing in Nature correlate those weakening wind patterns during the last 30 years to a buildup of aerosols in the atmosphere over India, which deflect sunlight away from the surface, creating dimming at ground level. They say this dimming may be responsible for more intense…

8,000 years ago, which is basically yesterday in geological time, a now-vanished glacial lake covered a huge expanse of today's Canadian prairie and the rich farmland in the Red River Valley. As big as Hudson Bay, the lake was fed by melting glaciers as they receded at the end of the last ice age. At its largest, Glacial Lake Agassiz, as it is known, covered most of the Canadian province of Manitoba, plus a good part of western Ontario and the Minnesota-North Dakota border.On October 10th, not far from the ancient shore of Lake Agassiz, University of Cincinnati Professor of Geology Thomas…