Snow and Ice Cover and Climate Sensitivity

1995 ◽  
pp. 189-198 ◽  
Author(s):  
J. Oerlemans ◽  
R. Bintanja
Keyword(s):  
Climate Sensitivity ◽  
Ice Cover ◽  
Snow And Ice

Geospatially extracting snow and ice cover distribution in the cold arid zone of India

2019 ◽  
Vol 11 (S1) ◽  
pp. 84-99
Author(s):  
Mahesh Kumar Gaur ◽  
R. K. Goyal ◽  
M. S. Raghuvanshi ◽  
R. K. Bhatt ◽  
M. Pandian ◽  
...  
Keyword(s):  
Arid Zone ◽  
Ice Cover ◽  
Snow And Ice

scholarly journals Modelling Global Ice and Climate Changes Through the Ice Ages

1990 ◽  
Vol 14 ◽  
pp. 23-27 ◽  
Author(s):  
W.F. Budd ◽  
P. Rayner
Keyword(s):  
Sea Ice ◽  
Ice Sheets ◽  
Ice Cover ◽  
Balance Model ◽  
Annual Variations ◽  
Sensitivity Tests ◽  
Mixed Layer Ocean ◽  
Wide Range ◽  
Sensitivity Studies ◽  
Snow And Ice

A global energy balance model has been developed which includes an interactive mixed layer ocean, sea ice, and snow and ice cover on the land. A full annual cycle is included and the model provides a close simulation to the variation of surface temperature through the year over land and over ocean as a function of latitude. The present annual variations of sea ice and snow on the ground are also well simulated. The model has been used for a wide range of sensitivity tests which include variations of the solar constant, surface albedos, and the effects of feed-back, or absence of feed-back, in the reponse of the snow and ice cover. Studies have been made of the model’s response to the long term variations in the Earth’s Orbital characteristics such as changes in the perihelion, the obliquity and the eccentricity as well as various combined changes. Independent sensitivity studies of the response of the model to the presence of the large ice sheets in the northern hemisphere have also been carried out. A series of model runs have been performed to study climatic changes around the globe from 160 000 years Β.P. (Before Present) to the present. An examination is made of the impacts of the orbital changes alone, as well as with the feed-back from the large ice sheets.

The use of Satellite Imagery in Investigating the Dynamics of the Ice and Snow Cover Lake Baikal

2003 ◽  
Vol 34 (1-2) ◽  
pp. 33-50 ◽  
Author(s):  
S.V. Semovski ◽  
N. Yu Mogilev
Keyword(s):  
Snow Cover ◽  
Lake Baikal ◽  
Satellite Imagery ◽  
Ice Cover ◽  
Unfrozen Water ◽  
Processing Strategy ◽  
Noaa Avhrr ◽  
Satellite Information ◽  
Process Studies ◽  
Snow And Ice

The generation and sample applications of a set of multispectral remotely sensed products for investigations of Lake Baikal's ice cover variability are described. During the period from mid-January to the end of April, the lake is completely covered with ice, and by analyzing satellite information it is possible to investigate in detail the distribution and dynamics of the main types of snow and ice cover. Different ice cover classes and unfrozen water distributions are estimated from calibrated and navigated NOAA AVHRR 1.1-km imagery of Lake Baikal for January 1994 through May 1999. The processing strategy and characteristics of the products are reviewed. The utility of this type of multiparameter dataset for modelling applications and process studies is discussed. ERS SAR and Resurs images are used for detailed representation of different ice classes distributions.

The significance of global snow and ice cover for global change studies

GeoJournal ◽  
1992 ◽  
Vol 27 (3) ◽  
pp. 293-297 ◽  
Author(s):  
Roger G. Barry
Keyword(s):  
Global Change ◽  
Ice Cover ◽  
Snow And Ice

scholarly journals Evaluation and climate sensitivity of the PlaSim v.17 Earth System Model coupled with ocean model components of different complexity

2020 ◽  
Author(s):  
Michela Angeloni ◽  
Elisa Palazzi ◽  
Jost von Hardenberg
Keyword(s):  
Sea Ice ◽  
Heat Transport ◽  
Mixed Layer ◽  
Climate Sensitivity ◽  
Ice Cover ◽  
Earth System Model ◽  
Sea Surface ◽  
System Model ◽  
Earth System ◽  
Feedback Mechanisms

Abstract. A set of experiments is performed with coupled atmosphere-ocean configurations of the Planet Simulator, an Earth-system Model of Intermediate Complexity (EMIC), in order to identify under which set of parameters the model output better agrees with observations and reanalyses of the present climate. Different model configurations are explored, in which the atmospheric module of PlaSim is coupled with two possible ocean models, either a simple mixed-layer (ML) ocean with a diffusive transport parameterization or a more complex dynamical Large-Scale Geostrophic (LSG) ocean, together with a sea-ice module. In order to achieve a more realistic representation of present-day climate, we performed a preliminary tuning of the oceanic horizontal diffusion coefficient for the ML ocean and of the vertical oceanic diffusion profile when using LSG. Model runs under present-day conditions are compared, in terms of surface air temperature, sea surface temperature, sea ice cover, precipitation, radiation fluxes, ocean circulation, with a reference climate from observations and reanalyses. Our results indicate that, in all configurations, coupled PlaSim configurations are able to reproduce the main characteristics of the climate system, with the exception of the Southern Ocean region in the PlaSim-LSG model, where surface air and sea surface temperatures are warm-biased and sea ice cover is by consequence highly underestimated. The resulting sets of tuned parameters are used to perform a series of model equilibrium climate sensitivity (ECS) experiments, with the aim to identify the main mechanisms contributing to differences between the different configurations and leading to elevated values of ECS. In fact, high resulting global ECS values are found, positioned in the upper range of CMIP5 and recent CMIP6 estimates. Our analysis shows that a significant contribution to ECS is given by the sea-ice feedback mechanisms and by details of the parameterization of meridional oceanic heat transport. In particular, the configurations using a diffusive heat transport in the mixed layer present an important sensitivity in terms of radiative forcing to changes in sea-ice cover, leading to an important contribution of sea-ice feedback mechanisms to ECS.

scholarly journals An enhancement to sea ice motion and age products

2019 ◽  
Author(s):  
Mark A. Tschudi ◽  
Walter N. Meier ◽  
J. Scott Stewart
Keyword(s):  
Sea Ice ◽  
Ice Cover ◽  
The Arctic ◽  
Significant Shift ◽  
High Concentration ◽  
Sea Ice Extent ◽  
Previous Version ◽  
Arctic Ice ◽  
The Impact ◽  
Snow And Ice

Abstract. A new version of the sea ice motion and age products distributed at the National Snow and Ice Data Center's NASA Snow and Ice Distributed Active Archive Center has been developed. The new version, 4.0, includes several significant upgrades in processing, corrects known issues with the previous version, and updates the time series through 2018, with regular updates planned for the future. Here, we provide a history of the product development, discuss the improvements to the algorithms that create these products, and compare the Version 4 products to the previous version. While Version 4 algorithm changes were significant, the impact on the products is relatively minor, particularly for more recent years. Trends in motion and age are not substantially different between the versions. Changes in sea ice motion and age derived from the product show a significant shift in the Arctic ice cover, from a pack with a high concentration of older ice, to a sea ice cover dominated by first-year ice, which is more susceptible to summer melt. We also observe an increase in the speed of the ice in recent years, which is anticipated with the annual decrease in sea ice extent.

scholarly journals A Method for Assessing the State of the Snow and Ice Cover by the Brewster Angle

2021 ◽  
Vol 24 (1) ◽  
pp. 34-47
Author(s):  
V. G. Mashkov ◽  
V. A. Malyshev ◽  
P. A. Fedyunin
Keyword(s):  
Depth Resolution ◽  
Ice Cover ◽  
Brewster Angle ◽  
Ultra Wideband ◽  
Methodological Error ◽  
Fresnel Reflection ◽  
Vertical Polarization ◽  
Helicopter Flight ◽  
Remote Assessment ◽  
Snow And Ice

Introduction. Landing is the most challenging and dangerous part of the helicopter flight. The development of systems facilitating safe landing is a priority task for both Russian and foreign engineering companies. Landing on unprepared sites covered with snow and ice may be determined by the need to deliver cargo and ammunition in combat conditions, during search and rescue operations, evacuations of victims, etc.Aim. Development of a method for remote assessment of the snow and ice cover based on the results of oblique sensing of the underlying surface with a radio signal with vertical polarization.Materials and methods. In the MatLab environment, the authors conducted numerical simulations of Fresnel reflection coefficients of echo signals with vertical polarization in the 40–90 degree sensing range in the operating frequency range when solving the direct and inverse problem of reconstruction of the parameters of snow and ice layers.Results. Intervals of the Brewster angle values were obtained at which the value of the Fresnel reflection coefficient from the boundaries of the snow and ice cover takes minimal. Thus, was found to be – 47...55°, – 55...58° and – 58...61° for dry snow, dry firn and dry ice, respectively. The depth resolution when using an ultra-wideband LFM signal with a frequency from 2 to 8 GHz is about 4 cm. The methodological error in determining the dielectric permittivity of layers by the Brewster angle comprises not more than 3 %.Conclusion. The error in determining the relative permittivity and the depth of k layers under an increase in the RMS values of the noise level from 3.8 to 4.8 with a step of 0.1 for 100 implementations of each with a probability of 0.95 does not exceed 10 %, which confirms the validity of this method. The implementation of which allows you to automate the process of evaluating the possibility of a safe landing, thereby reducing the decision-making time and increasing the level of safety.

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