Papers on ice-albedo feedback

This is a list of papers on ice-albedo feedback. The list is not complete, and will most likely be updated in the future in order to make it more thorough and more representative.

UPDATE (October 23, 2010): Flanner et al. (2011) added. Thanks to Barry for pointing it out (see the discussion section).
UPDATE (October 23, 2010): Meehl & Washington (1990) added.

Radiative forcing and albedo feedback from the Northern Hemisphere cryosphere between 1979 and 2008 – Flanner et al. (2011) “The extent of snow cover and sea ice in the Northern Hemispherehas declined since 1979, coincident with hemispheric warming and indicative of a positive feedback of surface reflectivity on climate. This albedo feedback of snow on land has been quantified from observations at seasonal timescales, and century-scale feedback has been assessed using climate models. However, the total impact of the cryosphere on radiative forcing and albedo feedback has yet to be determined from measurements. Here we assess the influence of the Northern Hemisphere cryosphere on Earth’s radiation budget at the top of the atmosphere—termed cryosphere radiative forcing—by synthesizing a variety of remote sensing and field measurements. We estimate mean Northern Hemisphere forcing at −4.6 to −2.2 W m⁻², with a peak in May of −9.0±2.7 W m⁻². We find that cyrospheric cooling declined by 0.45 W m⁻² from 1979 to 2008, with nearly equal contributions from changes in land snow cover and sea ice. On the basis of these observations, we conclude that the albedo feedback from the Northern Hemisphere cryosphere falls between 0.3 and 1.1 W m⁻² K⁻¹, substantially larger than comparable estimates obtained from 18 climate models.” M. G. Flanner, K. M. Shell, M. Barlage, D. K. Perovich & M. A. Tschudi, Nature Geoscience 4,151–155(2011)doi:10.1038/ngeo1062. [Full text]

The Global Radiative Impact of the Sea-Ice-Albedo Feedback in the Arctic – Hudson (2009) “In this study I present calculations of the global radiative impact of the reduction in Earth’s albedo resulting from reduced sea-ice cover in the Arctic. The intended result is a number, in W m^-2, that represents the total increase in absorbed solar radiation due to the reduction in Arctic sea-ice cover, averaged over the globe and over the year. … Rather than try to determine this forcing with a model, in which the assumptions and approximations are difficult to see and understand, I use representative datasets and calculate the effect with relatively simple math. … The details of the calculation, including assumptions and approximations will be presented, along with a range of results for current and future changes, as well as for an estimate on the upper bound: a global-annual mean of about 0.7 W m^-2.”

Sea Ice-Albedo Climate Feedback Mechanism – Curry et al. (1995) “The sea ice-albedo feedback mechanism over the Arctic Ocean multiyear sea ice is investigated by conducting a series of experiments using several one-dimensional models of the coupled sea ice-atmosphere system. In its simplest form, ice-albedo feedback is thought to be associated with a decrease in the areal cover of snow and ice and a corresponding increase in the surface temperature, further decreasing the areal cover of snow and ice. It is shown that the sea ice-albedo feedback can operate even in multiyear pack ice, without the disappearance of this ice, associated with internal processes occurring within the multiyear ice pack (e.g., duration of the snow cover, ice thickness, ice distribution, lead fraction, and melt pond characteristics). … The inclusion of melt ponds significantly strengthens the ice-albedo feedback, while the ice thickness distribution decreases the strength of the modeled sea ice-albedo feedback. It is emphasized that accurately modeling present-day sea ice thickness is not adequate for a sea ice parameterization; the correct physical processes must be included so that the sea ice parameterization yields correct sensitivities to external forcing.” [Full text]

CO₂ climate sensitivity and snow-sea-ice albedo parameterization in an atmospheric GCM coupled to a mixed-layer ocean model – Meehl & Washington (1990) “The snow-sea-ice albedo parameterization in an atmospheric general circulation model (GCM), coupled to a simple mixed-layer ocean and run with an annual cycle of solar forcing, is altered from a version of the same model described by Washington and Meehl (1984). The model with the revised formulation is run to equilibrium for 1 × CO₂ and 2 × CO₂ experiments. The 1 ×CO₂ (control) simulation produces a global mean climate about 1° warmer than the original version, and sea-ice extent is reduced. The model with the altered parameterization displays heightened sensitivity in the global means, but the geographical patterns of climate change due to increased carbon dioxide (CO₂) are qualitatively similar. The magnitude of the climate change is affected, not only in areas directly influenced by snow and ice changes but also in other regions of the globe, including the tropics where sea-surface temperature, evaporation, and precipitation over the oceans are greater. With the less-sensitive formulation, the global mean surface air temperature increase is 3.5 °C, and the increase of global mean precipitation is 7.12%. The revised formulation produces a globally averaged surface air temperature increase of 4.04 °C and a precipitation increase of 7.25%, as well as greater warming of the upper tropical troposphere. Sensitivity of surface hydrology is qualitatively similar between the two cases with the larger-magnitude changes in the revised snow and ice-albedo scheme experiment. Variability of surface air temperature in the model is comparable to observations in most areas except at high latitudes during winter. In those regions, temporal variation of the sea-ice margin and fluctuations of snow cover dependent on the snow-ice-albedo formulation contribute to larger-than-observed temperature variability. This study highlights an uncertainty associated with results from current climate GCMs that use highly parameterized snow-sea-ice albedo schemes with simple mixed-layer ocean models.” Gerald A. Meehl and Warren M. Washington, Climatic Change, 1990, Volume 16, Number 3, 283-306, DOI: 10.1007/BF00144505.

Ice-albedo feedback in a CO₂-doubling simulation – Dickinson et al. (1987) “We estimate the feedback of sea-ice change to the warming from CO₂-doubling according to the simulation of Washington and Meehl (1984). Without ice-snow albedo feedback, their global warming of 3.5 °C would have been 2.2. °C according to our estimate of the ice-snow feedback. About 80% of the albedo change from ice and snow occurred in the Southern Hemisphere.”

Effect of Ice-Albedo Feedback on Global Sensitivity in a One-Dimensional Radiative-Convective Climate Model – Wang & Stone (1980) “The feedback between ice albedo and temperature is included in a one-dimensional radiative-convective climate model. The effect of this feedback on global sensitivity to changes in solar constant is studied for the current climate conditions. This ice-albedo feedback amplifies global sensitivity by 26 and 39%, respectively, for assumptions of fixed cloud altitude and fixed cloud temperature. The global sensitivity is not affected significantly if the latitudinal variations of mean solar zenith angle and cloud cover are included in the global model.” [Full text]

Energy Balance Climate Models: A Reappraisal of Ice-Albedo Feedback – Lian & Cess (1977) “Disagreement exists, with regard to different types of climate models, concerning the influence of ice-albedo feedback upon the stability of the present global climate. In view of this we have reexamined the empirical relationship between zonal albedo and temperature for use in zonally averaged energy-balance climate models, and conclude that ice-albedo feedback constitutes a relatively mild climate feedback mechanism, amplifying global climate sensitivity by roughly 25%.” [Full text]

Regional effects

Sea Ice-Albedo Feedback and Nonlinear Arctic Climate Change – Winton (2008) “The potential for sea ice―albedo feedback to give rise to nonlinear climate change in the Arctic Ocean region, defined as a nonlinear relationship between polar and global temperature change or, equivalently, a time-varying polar amplification, is explored in the Intergovernmental Panel on Climate Change climate models. Five models supplying Special Report on Emissions Scenario A1B ensembles for the 21st century are examined, and very linear relationships are found between polar and global temperatures (indicating linear polar region climate change) and between polar temperature and albedo (the potential source of nonlinearity). … Atmospheric heat transport exerts a strong cooling effect during the transition to annually ice-free conditions, counteracting the albedo change. Specialized experiments with atmosphere-only and coupled models show that the main damping mechanism for sea ice region surface temperature is reduced upward heat flux through the adjacent ice-free oceans resulting in reduced atmospheric heat transport into the region.” [Full text]

Impact of ice-albedo feedback on hemispheric scale sea-ice melting rates in the Antarctic using Multi-frequency Scanning Microwave Radiometer data – Mitra et al. (2008) “In this study the Multi-frequency Scanning Microwave Radiometer (MSMR) brightness temperature data over the Antarctic/Southern Ocean region is used to calculate the weekly sea-ice extents, during the melting phase from August 1999 to March 2000 to quantitatively estimate the melting rates of sea-ice on a hemispheric scale. … The observed melting rate behaviour indicates that apart from the seasonal cycle of solar irradiance, it is controlled by other mechanisms like the icealbedo feedback. The present study estimates the feedback factor, response time and acceleration in the melting rate, which are important towards a better quantitative understanding of the future of Antarctic sea-ice variability, and the climate trends in the context of global warming.”

What drove the dramatic retreat of arctic sea ice during summer 2007? – Zhang et al. (2008) “A model study has been conducted of the unprecedented retreat of arctic sea ice in the summer of 2007. It is found that preconditioning, anomalous winds, and ice-albedo feedback are mainly responsible for the retreat.” [Full text]

Increasing solar heating of the Arctic Ocean and adjacent seas, 1979–2005: Attribution and role in the ice-albedo feedback – Perovich et al. (2007) “This study addresses how the amount of solar energy absorbed in areas of open water in the Arctic Basin has varied spatially and temporally over the past few decades. A synthetic approach was taken, combining satellite-derived ice concentrations, incident irradiances determined from reanalysis products, and field observations of ocean albedo over the Arctic Ocean and the adjacent seas. Results indicate an increase in the solar energy deposited in the upper ocean over the past few decades in 89% of the region studied. The largest increases in total yearly solar heat input, as much as 4% per year, occurred in the Chukchi Sea and adjacent areas.” [Full text]

Lake Superior summer water temperatures are increasing more rapidly than regional air temperatures: A positive ice-albedo feedback – Austin & Colman (2007) “Lake Superior summer (July–September) surface water temperatures have increased approximately 2.5°C over the interval 1979–2006, equivalent to a rate of (11 ± 6) × 10−2°C yr−1, significantly in excess of regional atmospheric warming. This discrepancy is caused by declining winter ice cover, which is causing the onset of the positively stratified season to occur earlier at a rate of roughly a half day per year. An earlier start of the stratified season significantly increases the period over which the lake warms during the summer months, leading to a stronger trend in mean summer temperatures than would be expected from changes in summer air temperature alone.” [Full text]

Observational evidence of a hemispheric-wide ice–ocean albedo feedback effect on Antarctic sea-ice decay – Nihashi & Cavalieri (2006) “The effect of ice–ocean albedo feedback (a kind of ice-albedo feedback) on sea-ice decay is demonstrated over the Antarctic sea-ice zone from an analysis of satellite-derived hemispheric sea ice concentration and European Centre for Medium-Range Weather Forecasts (ERA-40) atmospheric data for the period 1979–2001. Sea ice concentration in December (time of most active melt) correlates better with the meridional component of the wind-forced ice drift (MID) in November (beginning of the melt season) than the MID in December. This 1 month lagged correlation is observed in most of the Antarctic sea-ice covered ocean. Daily time series of ice concentration show that the ice concentration anomaly increases toward the time of maximum sea-ice melt. These findings can be explained by the following positive feedback effect: once ice concentration decreases (increases) at the beginning of the melt season, solar heating of the upper ocean through the increased (decreased) open water fraction is enhanced (reduced), leading to (suppressing) a further decrease in ice concentration by the oceanic heat. Results obtained from a simple ice–ocean coupled model also support our interpretation of the observational results. This positive feedback mechanism explains in part the large interannual variability of the sea-ice cover in summer.”

Amplified Arctic climate change: What does surface albedo feedback have to do with it? – Winton (2006) “Forcings and feedbacks that impact the warming response are estimated for both Arctic and global regions based on standard model diagnostics. … SAF [surface albedo feedback] is shown to be a contributing, but not a dominating, factor in the simulated Arctic amplification and its intermodel variation.” [Full text]

Hydraulic controls of summer Arctic pack ice albedo – Eicken et al. (2004) “Linkages between albedo, surface morphology, melt pond distribution, and properties of first-year and multiyear sea ice have been studied at two field sites in the North American Arctic between 1998 and 2001. It is shown that summer sea-ice albedo depends critically on surface melt-pond hydrology, controlled by melt rate, ice permeability, and topography. Remarkable short-term and interannual variability in pond fraction varying by more than a factor of 2 and hence area-averaged albedo (varying between 0.28 and 0.49 over the period of a few days) were observed to be forced by millimeter to centimeter changes in pond water level. … Our work indicates that ice-albedo prediction in large-scale models with conventional methods is inherently difficult, if not impossible. However, a hydrological model, incorporating measured statistics of ice topography, reproduces observed pond features and variability, pointing toward an alternative approach in predicting ice albedo in numerical simulations.” [Full text]

Seasonal evolution of the albedo of multiyear Arctic sea ice – Perovich et al. (2002) “As part of ice albedo feedback studies during the Surface Heat Budget of the Arctic Ocean (SHEBA) field experiment, we measured spectral and wavelength-integrated albedo on multiyear sea ice. Measurements were made every 2.5 m along a 200-m survey line from April through October. Initially, this line was completely snow covered, but as the melt season progressed, it became a mixture of bare ice and melt ponds. Observed changes in albedo were a combination of a gradual evolution due to seasonal transitions and abrupt shifts resulting from synoptic weather events. There were five distinct phases in the evolution of albedo: dry snow, melting snow, pond formation, pond evolution, and fall freeze-up. In April the surface albedo was high (0.8–0.9) and spatially uniform. By the end of July the average albedo along the line was 0.4, and there was significant spatial variability, with values ranging from 0.1 for deep, dark ponds to 0.65 for bare, white ice.”

Applications of SHEBA/FIRE data to evaluation of snow/ice albedo parameterizations – Curry et al. (2001) “Climate models use a wide variety of parameterizations for surface albedos of the ice-covered ocean. … Observations obtained in the Arctic Ocean during 1997–1998 in conjunction with the Surface Heat Budget of the Arctic Ocean (SHEBA) and FIRE Arctic Clouds Experiment provide a unique data set against which to evaluate parameterizations of sea ice surface albedo. … Results show that these parameterizations yield very different representations of the annual cycle of sea ice albedo. … The baseline sea ice characteristics and strength of the ice-albedo feedback are compared for the simulations of the different surface albedos.” [Full text]