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the First International Satellite Cloud Climatology Project (ISCCP) Regional Experiment (FIRE), Cahalan et al. found a value of ∼+0.09 as representative of the PPH albedo bias at visible wavelengths. Subsequent observationally based work ( Barker 1996 ; Oreopoulos and Davies 1998 ; Pincus et al. 1999 ; Rossow et al. 2002 ) provided additional estimates of average PPH albedo bias that ranged from +0.02 to +0.3 depending on spectral range, cloud type, spatial resolution of the satellite
the First International Satellite Cloud Climatology Project (ISCCP) Regional Experiment (FIRE), Cahalan et al. found a value of ∼+0.09 as representative of the PPH albedo bias at visible wavelengths. Subsequent observationally based work ( Barker 1996 ; Oreopoulos and Davies 1998 ; Pincus et al. 1999 ; Rossow et al. 2002 ) provided additional estimates of average PPH albedo bias that ranged from +0.02 to +0.3 depending on spectral range, cloud type, spatial resolution of the satellite
1. Introduction Snow-albedo feedback (SAF) enhances Northern Hemisphere (NH) extratropical climate sensitivity in climate change simulations ( Budyko 1969 ; Sellers 1969 ; Schneider and Dickinson 1974 ; Robock 1983 ; Cess et al. 1991 ; Randall et al. 1994 ; Hall 2004 ) because of two changes in the snowpack as surface air temperature ( T s ) increases ( Robock 1985 ). First snow cover shrinks, and where it does it generally reveals a land surface that is much less reflective of solar
1. Introduction Snow-albedo feedback (SAF) enhances Northern Hemisphere (NH) extratropical climate sensitivity in climate change simulations ( Budyko 1969 ; Sellers 1969 ; Schneider and Dickinson 1974 ; Robock 1983 ; Cess et al. 1991 ; Randall et al. 1994 ; Hall 2004 ) because of two changes in the snowpack as surface air temperature ( T s ) increases ( Robock 1985 ). First snow cover shrinks, and where it does it generally reveals a land surface that is much less reflective of solar
1. Introduction The ratio of reflected to incident shortwave radiation at the top of the atmosphere (TOA), the earth’s planetary albedo, is a function of climate state and exerts a profound influence on the earth’s climate. As a reference point, Budyko (1969) postulated that a change in global average planetary albedo of less than 0.02 units could cause global glaciation of the climate system. The radiative forcing associated with a doubling of carbon dioxide above the preindustrial
1. Introduction The ratio of reflected to incident shortwave radiation at the top of the atmosphere (TOA), the earth’s planetary albedo, is a function of climate state and exerts a profound influence on the earth’s climate. As a reference point, Budyko (1969) postulated that a change in global average planetary albedo of less than 0.02 units could cause global glaciation of the climate system. The radiative forcing associated with a doubling of carbon dioxide above the preindustrial
1. Introduction Surface albedo is one of the most important parameters that affect the earth’s surface energy budget. It is a major source of uncertainties in radiative transfer calculations. In this study we use the U.S. Department of Energy Atmospheric Radiation Measurement (ARM) Program ( Stokes and Schwartz 1994 ; Ackerman and Stokes 2003 ) and the National Oceanic and Atmospheric Administration Surface Radiation Budget Network (SURFRAD) ( Augustine et al. 2000 ) observations to evaluate
1. Introduction Surface albedo is one of the most important parameters that affect the earth’s surface energy budget. It is a major source of uncertainties in radiative transfer calculations. In this study we use the U.S. Department of Energy Atmospheric Radiation Measurement (ARM) Program ( Stokes and Schwartz 1994 ; Ackerman and Stokes 2003 ) and the National Oceanic and Atmospheric Administration Surface Radiation Budget Network (SURFRAD) ( Augustine et al. 2000 ) observations to evaluate
1. Introduction Surface albedo, the ratio of the total outgoing to total incoming solar radiation at the earth’s surface, often constrained to wavelengths in the range of 0.3–3 μ m, is one of the most important factors controlling the amount of energy available to drive daytime surface exchange processes. Thus, surface albedo determines the total amount of energy available for evaporation, sensible heat flux, gas exchange and, through these, more generally earth’s climate system ( Lofgren 1995
1. Introduction Surface albedo, the ratio of the total outgoing to total incoming solar radiation at the earth’s surface, often constrained to wavelengths in the range of 0.3–3 μ m, is one of the most important factors controlling the amount of energy available to drive daytime surface exchange processes. Thus, surface albedo determines the total amount of energy available for evaporation, sensible heat flux, gas exchange and, through these, more generally earth’s climate system ( Lofgren 1995
1. Introduction Land surface albedo is a major driver of climate change ( Bonan 2008 ; Wielicki et al. 2005 ), but climate models rarely incorporate projected albedo changes from future land use ( Oleson et al. 2003 ; Tian et al. 2004 ). This is largely because of a continued poor understanding of the historic drivers of albedo change. Certain land-cover transitions, such as boreal and tropical deforestation, drive relatively well understood albedo changes that have been evaluated
1. Introduction Land surface albedo is a major driver of climate change ( Bonan 2008 ; Wielicki et al. 2005 ), but climate models rarely incorporate projected albedo changes from future land use ( Oleson et al. 2003 ; Tian et al. 2004 ). This is largely because of a continued poor understanding of the historic drivers of albedo change. Certain land-cover transitions, such as boreal and tropical deforestation, drive relatively well understood albedo changes that have been evaluated
1. Introduction Surface albedo is a measure of the proportion of total incoming solar radiation reflected by the earth’s surface. It determines the amount of solar energy absorbed by the earth’s surface that drives surface hydrological and biochemical processes, influences productivity of the terrestrial and aquatic ecosystems, and affects the atmospheric circulation. Multispectral surface albedo and its variability are important for global climate model (GCM) development, atmospheric radiation
1. Introduction Surface albedo is a measure of the proportion of total incoming solar radiation reflected by the earth’s surface. It determines the amount of solar energy absorbed by the earth’s surface that drives surface hydrological and biochemical processes, influences productivity of the terrestrial and aquatic ecosystems, and affects the atmospheric circulation. Multispectral surface albedo and its variability are important for global climate model (GCM) development, atmospheric radiation
-cover changes. Atmosphere–land surface feedback processes associated with variations in the albedo of dryland environments may be equally as important as soil moisture feedback processes for simulating droughts ( Evans et al. 2017 ). Although many studies have investigated impacts of ice, snow, and vegetation cover changes on surface albedo, less attention has been placed on changes arising from soil moisture or seasonal water variations (e.g., Chen et al. 2015 ; Ming et al. 2015 ; Li et al. 2018
-cover changes. Atmosphere–land surface feedback processes associated with variations in the albedo of dryland environments may be equally as important as soil moisture feedback processes for simulating droughts ( Evans et al. 2017 ). Although many studies have investigated impacts of ice, snow, and vegetation cover changes on surface albedo, less attention has been placed on changes arising from soil moisture or seasonal water variations (e.g., Chen et al. 2015 ; Ming et al. 2015 ; Li et al. 2018
1. Introduction The albedo, representing the fraction of backscattered solar radiant flux at any relevant level, is used to evaluate the distribution of solar energy between various components of the geophysical systems and in particular the fractions absorbed in the atmosphere, vegetation, and soil layers. When estimated at the level of the surface, this quantity provides a lower-boundary condition for the atmosphere (itself related to latent and sensible heat fluxes in the atmospheric
1. Introduction The albedo, representing the fraction of backscattered solar radiant flux at any relevant level, is used to evaluate the distribution of solar energy between various components of the geophysical systems and in particular the fractions absorbed in the atmosphere, vegetation, and soil layers. When estimated at the level of the surface, this quantity provides a lower-boundary condition for the atmosphere (itself related to latent and sensible heat fluxes in the atmospheric
. Pointing out that this interhemispheric albedo symmetry exists in more recent satellite records, Voigt et al. (2013) partitioned Earth into pairs of random halves and measured the difference in mean reflected radiation in each pair, finding that only 3% of pairs exhibit the degree of symmetry observed in Earth’s reflected radiation. This suggests that the observed symmetry and spatial distribution of albedo does not result from a high number of spatial degrees of freedom (i.e., that the albedo field
. Pointing out that this interhemispheric albedo symmetry exists in more recent satellite records, Voigt et al. (2013) partitioned Earth into pairs of random halves and measured the difference in mean reflected radiation in each pair, finding that only 3% of pairs exhibit the degree of symmetry observed in Earth’s reflected radiation. This suggests that the observed symmetry and spatial distribution of albedo does not result from a high number of spatial degrees of freedom (i.e., that the albedo field
