CAMBRIDGE - Old Sol these days is showing a strikingly bland face, one nearly unmarred by the usual wild magnetic storms, whipsawing coronal loops, and fiery plasma ejections.
“The sun is in the pits of the deepest solar minimum in almost 100 years,’’ said Madhulika Guhathakurta, lead program scientist for NASA’s Living With A Star program, whose focus is solar variability and its effects on the earth.
From the earth’s perspective, scientists say, the periodic lull in the sun’s activity means cosmic rays reaching our section of the solar system are way up, the planet’s ionosphere is way down, and the minimum may be producing some small but still important counteraction to climate change - though that is controversial.
As world leaders, eco-activists, and researchers gather in Copenhagen today for an international conference on global warming, the sun is providing cold comfort to more dire predictors of climate catastrophe.
Because of slightly decreased solar irradiance during the ongoing minimum cycle, the sun may be acting as a counterweight to the warming effects of greenhouse gases, according to recent research by Judith Lean of the Naval Research Lab and David Rindof NASA’s Goddard Institute for Space Studies.
The minimum, the research suggests, accounts for the flat temperature trend of this decade, which has flummoxed climate experts as thermometer readings fail to support forecasts of accelerated warming.
But even if a less radiant sun is partially offsetting global warmth caused by greenhouse gases, scientists stress that the overall effect is relatively slight - and almost certainly won’t last.
Can a lull in solar activity head off climate change? - The Boston Globe
“The sun is in the pits of the deepest solar minimum in almost 100 years,’’ said Madhulika Guhathakurta, lead program scientist for NASA’s Living With A Star program, whose focus is solar variability and its effects on the earth.
From the earth’s perspective, scientists say, the periodic lull in the sun’s activity means cosmic rays reaching our section of the solar system are way up, the planet’s ionosphere is way down, and the minimum may be producing some small but still important counteraction to climate change - though that is controversial.
As world leaders, eco-activists, and researchers gather in Copenhagen today for an international conference on global warming, the sun is providing cold comfort to more dire predictors of climate catastrophe.
Because of slightly decreased solar irradiance during the ongoing minimum cycle, the sun may be acting as a counterweight to the warming effects of greenhouse gases, according to recent research by Judith Lean of the Naval Research Lab and David Rindof NASA’s Goddard Institute for Space Studies.
The minimum, the research suggests, accounts for the flat temperature trend of this decade, which has flummoxed climate experts as thermometer readings fail to support forecasts of accelerated warming.
But even if a less radiant sun is partially offsetting global warmth caused by greenhouse gases, scientists stress that the overall effect is relatively slight - and almost certainly won’t last.
Can a lull in solar activity head off climate change? - The Boston Globe
