Not exact matches
One
aerosol,
black carbon, is of
increasing concern for Arctic nations worried about the pace of climate change in the far north, which is warming twice as fast as the global average.
Black carbon aerosols — particles of
carbon that rise into the atmosphere when biomass, agricultural waste, and fossil fuels are burned in an incomplete way — are important for understanding climate change, as they absorb sunlight, leading to higher atmospheric temperatures, and can also coat Arctic snow with a darker layer, reducing its reflectivity and leading to
increased melting.
The CARES field campaign was designed to
increase scientific knowledge about the evolution of
black carbon, primary organic
aerosols (POA), and secondary organic
aerosols (SOA) from both human - caused and natural (biogenic) sources.
[T] here have now been several recent papers showing much the same — numerous factors including: the
increase in positive forcing (CO2 and the recent work on
black carbon), decrease in estimated negative forcing (
aerosols), combined with the stubborn refusal of the planet to warm as had been predicted over the last decade, all makes a high climate sensitivity increasingly untenable.
Aerosols, or microscopic particles like soot or
black carbon in the air, occur naturally but have also been
increasing due to human activities since the industrial revolution.
«Observational analyses have shown the width of the tropical belt
increasing in recent decades as the world has warmed... we use a climate model with detailed
aerosol physics to show that
increases in heterogeneous warming agents — including
black carbon aerosols and tropospheric ozone — are noticeably better than greenhouse gases at driving expansion, and can account for the observed summertime maximum in tropical expansion.
Judith - Apart from the general anthro vs. natural disussion of sea ice, I'm always wondering: has anyone seriously considered / studied the possible anthropogenic contribution from NON-CO2 sources (
black carbon soot /
aerosol deposits on the ice surface,
increasing the albedo, melting the ice faster in the sun)?
«Comparing the amount of warming in the U.S. saved by reducing our greenhouse gas emissions by some 80 % to the amount of warming added in the U.S. by
increases in Asian
black carbon (soot)
aerosol emissions (at least according to Teng et al.) and there is no clear winner.
There is no evidence of regional cooling from
increases in asian
aerosols so it is logical to conclude that
black carbon and sulfates balance out.
In addition to reduced
aerosol cooling and
increased black carbon warming there is the IPCC's new admission of strong evidence for some mechanism of solar forcing substantially stronger than TSI (p. page 7 - 43): «Many empirical relationships have been reported between GCR or cosmogenic isotope archives and some aspects of the climate system (e.g., Bond et al., 2001; Dengel et al., 2009; Ram and Stolz, 1999).
Theoretically, coatings of essentially non-absorbing components such as organic
carbon or sulphate on strongly absorbing core components such as
black carbon can
increase the absorption of the composite
aerosol (e.g., Fuller et al., 1999; Jacobson, 2001a; Stier et al., 2006a), with results backed up by laboratory studies (e.g., Schnaiter et al., 2003).