Assessing the retrieval of cloud properties from radiation measurements over snow and ice

Munneke, Peter Kuipers; Reijmer, C. H.; Broeke, M. R. van den

doi:10.1002/joc.2114

Cited by 33 publications

(37 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The cloud cover generated by WRF clearly exceeds the approximations based on the AWS measurements of LW↓ and air temperature following Kuipers Munneke et al (2011). In contrast with our findings, Aas et al (2015) reported underestimation of the cloud optical depth at Ny Ålesund (20 m a.s.l.)…”

Section: Discussioncontrasting

confidence: 91%

Parameterizing Deep Water Percolation Improves Subsurface Temperature Simulations by a Multilayer Firn Model

et al. 2017

View full text Add to dashboard Cite

Deep preferential percolation of melt water in snow and firn brings water lower along the vertical profile than a laterally homogeneous wetting front. This widely recognized process is an important source of uncertainty in simulations of subsurface temperature, density, and water content in seasonal snow and in firn packs on glaciers and ice sheets. However, observation and quantification of preferential flow is challenging and therefore it is not accounted for by most of the contemporary snow/firn models. Here we use temperature measurements in the accumulation zone of Lomonosovfonna, Svalbard, done in April 2012-2015 using multiple thermistor strings to describe the process of water percolation in snow and firn. Effects of water flow through the snow and firn profile are further explored using a coupled surface energy balance -firn model forced by the output of the regional climate model WRF. In situ air temperature, radiation, and surface height change measurements are used to constrain the surface energy and mass fluxes. To account for the effects of preferential water flow in snow and firn we test a set of depth-dependent functions allocating a certain fraction of the melt water available at the surface to each snow/firn layer. Experiments are performed for a range of characteristic percolation depths and results indicate a reduction in root mean square difference between the modeled and measured temperature by up to a factor of two compared to the results from the default water infiltration scheme. This illustrates the significance of accounting for preferential water percolation to simulate subsurface conditions. The suggested approach to parameterization of the preferential water flow requires low additional computational cost and can be implemented in layered snow/firn models applied both at local and regional scales, for distributed domains with multiple mesh points.

show abstract

Section: Discussioncontrasting

confidence: 91%

Parameterizing Deep Water Percolation Improves Subsurface Temperature Simulations by a Multilayer Firn Model

et al. 2017

View full text Add to dashboard Cite

show abstract

“…AWS measurements near Svea show a range of clear‐sky LW in of 100 to 200 W m − 2 as a function of air temperature, with an increase up to 300 W m − 2 due to cloud forcing [ Kuipers Munneke et al ., ]. A similar range was also found by Town et al .…”

Section: Resultsmentioning

confidence: 99%

Meteorological regimes and accumulation patterns at Utsteinen, Dronning Maud Land, East Antarctica: Analysis of two contrasting years

et al. 2013

Self Cite

View full text Add to dashboard Cite

[1] Since February 2009, an automatic weather station (AWS) has been operating near Utsteinen Nunatak, north of the Sør Rondane Mountains, in Dronning Maud Land at the ascent to the East Antarctic Plateau. This paper gives an assessment of the meteorological conditions, radiative fluxes, and snow accumulation for the first 2 years of operation, 2009 to 2010, analyzed in terms of meteorological regimes. Three major meteorological regimescold katabatic, warm synoptic, and transitional synoptic-are identified using cluster analysis based on five parameters derived from the AWS measurements (wind speed, specific humidity, near-surface temperature inversion, surface pressure, and incoming longwave flux indicative of cloud forcing). For its location, the relatively mild climate at Utsteinen can be explained by the high frequency of synoptic events (observed 41%-48% of the time), and a lack of drainage of cold air from the plateau due to mountain sheltering. During the cold katabatic regime, a strong surface cooling leads to a strong near-surface temperature inversion buildup. A large difference in accumulation is recorded by the AWS for the first 2 years: 235 mm water equivalent in 2009 and 27 mm water equivalent in 2010. Several large accumulation events during the warm synoptic regime occurring mainly in winter were responsible for the majority of the accumulation in 2009. Mostly, small accumulation events occurred during 2010, frequently followed by snow removal. This interannual variability in snow accumulation at the site is related to the intensity of the local synoptic events as recorded by meteorological regime characteristics.

show abstract

“…The weakest winds are blowing from the NW and E at both stations. We computed cloud optical thickness using an algorithm that relates the observed SW ↓ to the theoretical clear-sky value of SW ↓ (Fitzpatrick et al, 2004), extrapolated to the winter months using a good correlation between cloud optical thickness and the longwave radiation balance in summer (Kuipers Munneke et al, 2010). The cloud cover at AWS 15 is generally optically thicker than at AWS 14 (Fig.…”

Section: Near-surface Meteorologymentioning

confidence: 99%

Near-surface climate and surface energy budget of Larsen C ice shelf, Antarctic Peninsula

et al. 2012

Self Cite

View full text Add to dashboard Cite

Abstract. Data collected by two automatic weather stations (AWS) on the Larsen C ice shelf, Antarctica, between 22 January 2009 and 1 February 2011 are analyzed and used as input for a model that computes the surface energy budget (SEB), which includes melt energy. The two AWSs are separated by about 70 km in the north-south direction, and both the near-surface meteorology and the SEB show similarities, although small differences in all components (most notably the melt flux) can be seen. The impact of subsurface absorption of shortwave radiation on melt and snow temperature is significant, and discussed. In winter, longwave cooling of the surface is entirely compensated by a downward turbulent transport of sensible heat. In summer, the positive net radiative flux is compensated by melt, and quite frequently by upward turbulent diffusion of heat and moisture, leading to sublimation and weak convection over the ice shelf. The month of November 2010 is highlighted, when strong westerly flow over the Antarctic Peninsula led to a dry and warm föhn wind over the ice shelf, resulting in warm and sunny conditions. Under these conditions the increase in shortwave and sensible heat fluxes is larger than the decrease of net longwave and latent heat fluxes, providing energy for significant melt.

show abstract

Assessing the retrieval of cloud properties from radiation measurements over snow and ice

Cited by 33 publications

References 41 publications

Parameterizing Deep Water Percolation Improves Subsurface Temperature Simulations by a Multilayer Firn Model

Parameterizing Deep Water Percolation Improves Subsurface Temperature Simulations by a Multilayer Firn Model

Meteorological regimes and accumulation patterns at Utsteinen, Dronning Maud Land, East Antarctica: Analysis of two contrasting years

Near-surface climate and surface energy budget of Larsen C ice shelf, Antarctic Peninsula

Contact Info

Product

Resources

About