Snow albedo refers to the reflectivity or whiteness of snow.
Full definition
Hall and Qu (2006) show that biases of a number of MMD models in reproducing the observed seasonal cycle of land snow cover (especially the spring melt) are tightly related to the large variations in
snow albedo feedback strength simulated by the same models in climate change scenarios.
Ibid., pp. 393 — 96; Yun Qian et al., «Effects of Soot - Induced
Snow Albedo Change on Snowpack and Hydrological Cycle in Western United States Based on Weather Research and Forecasting Chemistry and Regional Climate Simulations,» Journal of Geophysical Research, vol.
Evaluation of the MODIS (MOD10A1)
daily snow albedo product over the Greenland ice sheet.
New methods to
infer snow albedo from the MISR instrument with applications to the Greenland ice sheet.
So, not only is Steel's hypothesis about ice and
snow albedo unjustified, its most crucial point (the opposite trends in spring and autumn) is directly contrary to available evidence.
The inset in Figure 2d shows the individual greenhouse gases, tropospheric aerosols and the land surface plus
snow albedo components that combine to give the net anthropogenic forcing.
Paper: Reference: Yun Qian, William I. Gustafson Jr., L. Ruby Leung, Steven J. Ghan, Effects of soot -
induced snow albedo change on snowpack and hydrological cycle in western U.S. based on WRF chemistry and regional climate simulations, Journal of Geophysical Research - Atmospheres, 2009, doi: 10.1029 / 2008JD011039
Addressing the seasonal cycle biases would therefore provide a constraint that would reduce divergence in simulations
of snow albedo feedback under climate change.
My Figure 4 showed that when LU forcing was deducted, the excess of Historical forcing over the sum of the six individual forcings analysed by Marvel et al. almost exactly matched forcing from black carbon deposited on snow and ice (
Snow Albedo BC), a minor forcing included in the Historical simulations in addition to the six forcing analysed in Marvel et al..
The forcings illustrated here are from the well mixed greenhouse gases (GHGs)(CO2, CH4, N2O, CFCs), tropospheric and stratospheric O3, direct aerosol effects (from sulphates, nitrates, organic and black carbon), land use change, solar irradiance, volcanic aerosols, and various indirect effects (on clouds, stratospheric water vapour,
snow albedo etc.).
Hall, A. & Qu, X. Using the current seasonal cycle to constrain
the snow albedo feedback in future climate change.
snow albedo) was modified in the NorESM climate model, by replacing an approach based on spherical snow grains with an approach assuming nonspherical snow grains.
To better constrain the computation of
snow albedo in climate models, more comprehensive observations on both snow albedo and on other snow physical properties are needed.
The average albedo is 0.3 and
the snow albedo is 0.8.
Development and validation of
a snow albedo algorithm for the MODIS instrument.
Thus the BC -
snow albedo effect contributes to warming.
* Plus 3.51 w / sq m from well - mixed greenhouse gases, ozone, land use changes, black carbon,
snow albedo and aircraft contrails (anthropogenic)
There are good reasons to assume that important amplifying feedbacks, such as
the snow albedo feedback, become much weaker in warmer climates, which would result in an underestimation of climate sensitivity to CO2 doubling in such a regression.
Lean and Rind estimated the anthropogenic forcing based on the net effect of eight different components, including greenhouse gases, land use and
snow albedo (reflectivity) changes, and tropospheric aerosols.
However, possible use of seasonal
snow albedo feedback to evaluate snow albedo feedback under climate change conditions is of course dependent upon the realism of the correlation between the two feedbacks suggested by GCMs (Figure 8.16).
Models indicate increased boreal forest reduces the effects of
snow albedo and causes regional warming.