scholarly journals Arctic and Antarctic precipitation simulations produced by the NCAR community climate models

1995 ◽  
Vol 21 ◽  
pp. 117-122
Author(s):  
David H. Bromwich ◽  
Biao Chen ◽  
Ren-Yow Tzeng
Keyword(s):  
Moisture Transport ◽  
Climate Models ◽  
Climate Model ◽  
Polar Regions ◽  
Moisture Budget ◽  
Atmospheric Moisture ◽  
Atmospheric Moisture Budget ◽  
Antarctic Precipitation ◽  
Climatic Characteristics ◽  
Community Climate

Precipitation predictions from globai-climate models (GCMs) for the ice-covered Arctic Ocean and the ice sheets of Antarctica are among the most important aspects of the inferred response of the polar areas to climate change. It is generally recognized that the atmospheric hydrologic cycle, which includes precipitation as a key part, is one of the components of the climate system that GCMs do not handle particularly well.The present-day atmospheric-moisture budget poleward of 70° latitude in both hemispheres, as represented by two versions of the NCAR (U.S. National Center for Atmospheric Research) community climate model (CCM1 and CCM2), is compared with observational analyses. The quantities examined on the seasonal and annual timescales are precipitation, evaporation/sublimation and atmospheric poleward moisture transport. The results are discussed in terms of the physiographic and climatic characteristics of both polar regions and how the particular models handle moisture transport: CCM1 uses the positive-moisture fixer and CCM2 the semi- Lagrangian transport. A particularly important test both for models and for observations is the degree to which the independently determined moisture-budget quantities actually balance. Deficiencies of both observations and models are discussed.

scholarly journals Arctic and Antarctic precipitation simulations produced by the NCAR community climate models

1995 ◽  
Vol 21 ◽  
pp. 117-122 ◽  
Author(s):  
David H. Bromwich ◽  
Biao Chen ◽  
Ren-Yow Tzeng
Keyword(s):  
Moisture Transport ◽  
Climate Models ◽  
Climate Model ◽  
Polar Regions ◽  
Moisture Budget ◽  
Atmospheric Moisture ◽  
Atmospheric Moisture Budget ◽  
Antarctic Precipitation ◽  
Climatic Characteristics ◽  
Community Climate

Precipitation predictions from globai-climate models (GCMs) for the ice-covered Arctic Ocean and the ice sheets of Antarctica are among the most important aspects of the inferred response of the polar areas to climate change. It is generally recognized that the atmospheric hydrologic cycle, which includes precipitation as a key part, is one of the components of the climate system that GCMs do not handle particularly well. The present-day atmospheric-moisture budget poleward of 70° latitude in both hemispheres, as represented by two versions of the NCAR (U.S. National Center for Atmospheric Research) community climate model (CCM1 and CCM2), is compared with observational analyses. The quantities examined on the seasonal and annual timescales are precipitation, evaporation/sublimation and atmospheric poleward moisture transport. The results are discussed in terms of the physiographic and climatic characteristics of both polar regions and how the particular models handle moisture transport: CCM1 uses the positive-moisture fixer and CCM2 the semi- Lagrangian transport. A particularly important test both for models and for observations is the degree to which the independently determined moisture-budget quantities actually balance. Deficiencies of both observations and models are discussed.

Role of the Atmospheric Moisture Budget in Defining the Precipitation Seasonality of the Great Lakes Region

2021 ◽  
Vol 34 (2) ◽  
pp. 643-657
Author(s):  
Samar Minallah ◽  
Allison L. Steiner
Keyword(s):  
Great Lakes ◽  
Spatial Patterns ◽  
Moisture Transport ◽  
Transport Processes ◽  
Great Lakes Region ◽  
Moisture Budget ◽  
Atmospheric Moisture ◽  
Precipitation Seasonality ◽  
Atmospheric Moisture Budget

AbstractPrecipitation in the Great Lakes region has a distinct seasonal cycle that peaks in early summer, followed by a decline in August and a secondary peak in September. This seasonality is often not captured by models, which necessitates understanding of the driving mechanisms to ascertain the model biases. This study analyzes the atmospheric moisture budget using reanalysis datasets to assess the role of regional evapotranspiration and moisture influx from remote origins in defining the precipitation seasonality, and to understand how the Great Lakes modulate spatial patterns and magnitudes of these components. Specifically, the land–water thermal contrast yields large seasonal variations in the evaporative fluxes and creates distinctive localized spatial patterns of moisture flux divergence. We find considerable month-to-month variations in both evapotranspiration and the net moisture transport through the boundaries, where they play a cooperative (contrasting) role in amplifying (dampening) the moisture content available for precipitation and total precipitable water. Our seasonal analysis suggests that the misrepresentation of the budget quantities in models, for example, in simulation of moisture transport processes and parameterization schemes, can result in an anomalous precipitation behavior and, in some cases, violation of the atmospheric moisture mass balance, resulting in large residual magnitudes. We also identify conspicuous differences in the representation of moisture budget components in the various reanalyses, which can alter their representation of the regional hydroclimates.

Atmospheric moisture budget and floods in the Yangtze River basin, China

2008 ◽  
Vol 95 (3-4) ◽  
pp. 331-340 ◽  
Author(s):  
Zengxin Zhang ◽  
Qiang Zhang ◽  
Chongyu Xu ◽  
Chunling Liu ◽  
Tong Jiang
Keyword(s):  
River Basin ◽  
Yangtze River ◽  
Yangtze River Basin ◽  
Moisture Budget ◽  
The Yangtze River ◽  
Atmospheric Moisture ◽  
The Yangtze River Basin ◽  
Atmospheric Moisture Budget

Microphysics of Antarctic precipitation in climate models : recent advances and challenges

2020 ◽  
Author(s):  
Étienne Vignon ◽  
Josué Gehring ◽  
Simon P. Alexander ◽  
Georgia Sotiropoulou ◽  
Nikola Besic ◽  
...  
Keyword(s):  
Climate Models ◽  
Climate Model ◽  
Wrf Model ◽  
Supercooled Liquid ◽  
Surface Mass ◽  
Current Assessment ◽  
Climate Model Simulations ◽  
Microphysical Processes ◽  
Antarctic Precipitation ◽  
The Antarctic

<p align="justify"><span>The current assessment of the Antarctic surface mass balance mostly relies on reanalysis products or climate model simulations. The ability of models to reproduce the precipitation field at the regional and continental scales not only depends on the simulation of the atmospheric dynamics over the Southern Ocean and of the advection of moisture towards the ice sheet, but also on the representation of the microphysical processes that govern the formation and growth of ice crystals and snowflakes. This presentation reviews recent studies to stress the importance and challenges of evaluating the precipitation microphysics over Antarctica in climate models. It also discusses how recent observational campaigns including ground-based remote-sensing instruments can help pinpoint key processes that should be represented in models. We then present tangible examples of evaluation and improvement of microphysical schemes in the Polar WRF model thanks to radar and lidar observations acquired near Dumont d’Urville and Mawson stations on the Antarctic coast. Particular attention is devoted to three processes : i) the sublimation of snowfall within the katabatic layer that considerably reduces the amount of precipitation that actually reaches the surface ; ii) the snowflake aggregation responsible for rapid depletion of crystals within clouds ; iii) the generation of supercooled liquid water in frontal clouds that leads to crystal/snowflake riming. Such studies, albeit preliminary, could pave the way for further evaluations of clouds and precipitation in climate models in different Antarctic contexts, especially in the cold and pristine atmosphere of the Plateau.</span></p>

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