The principal tools used to model future climate change are General Circulation Models which are deterministic high resolution bottom-up models of the global atmosphere-ocean system that require large amounts of supercomputer time to generate results. But are these models a cost-effective way of predicting future climate change at the global level? In this paper we use modern econometric techni...

[1] A 1 horizontal resolution North Atlantic general circulation model (GCM) in the latitude band 4.5 S to 39.5 N is compared to, and then combined with, chlorofluorocarbon and tritium transient tracer data. The method of Lagrange multipliers (adjoint) is used. Tracer distribution within the model ocean interior is primarily sensitive to the flux through the open northern boundary. This flux is...

To estimate the sea level rise (SLR) originating from changes in surface mass balance (SMB) of the Greenland ice sheet (GrIS), we present 21st century climate projections obtained with the regional climate model MAR (Modèle Atmosphérique Régional), forced by output of three CMIP5 (Coupled Model Intercomparison Project Phase 5) general circulation models (GCMs). Our results indicate that in a wa...

Theoretical work and general circulation model (GCM) experiments suggest that themidlatitude jet stream’s interaction with large-scale topography can drive intraseasonal oscillations in large-scale atmospheric circulation patterns. In support of this theory, we present new observational evidence that mountain-induced torques play a key role in 15–30-day oscillations of the Northern Hemisphere c...

General circulation models (GCMs) of the climate system are powerful tools for understanding and predicting climate and climate change. The last glacial maximum (LGM) provides an extreme test of the model’s ability to simulate a change of climate, and allows us to increase our understanding of mechanisms of climate change. We have used a coupled high resolution ocean–atmosphere GCM (HadCM3) to ...

[1] The rate at which the outgoing longwave radiation (OLR) responds to perturbations in temperature and moisture plays a fundamental role in determining climate sensitivity. This study examines the clear-sky OLR sensitivities to temperature and water vapor, as quantified by its partial derivatives (radiative Jacobians). The Jacobians, as computed by the Geophysical Fluid Dynamics Laboratory (G...

This study evaluated 20 general circulation models (GCMs) of the Coupled Model Intercomparison Project, Phase 5 (CMIP5), which provide the prediction results for the period of 2006 to 2014, the period from which the observation data (the Global Precipitation Climatology Project (GPCP) data) are available. Both the GCM predictions of precipitation and the GPCP data were compared for three data s...

because of low spatial resolution and simplifications in meteorological processes in global circulation models, they cannot sufficiently simulate the weather, comparing to the regional models; then, spatial and temporal downscaling of the gcm outputs are needed for decreasing errors of the global circulation models. there are two methods of downscaling: statistical and dynamic. weather generato...

A new practical application of neural network (NN) techniques to environmental numerical modeling has been developed. Namely, a new type of numerical model, a complex hybrid environmental model based on a synergetic combination of deterministic and machine learning model components, has been introduced. Conceptual and practical possibilities of developing hybrid models are discussed in this pap...

The method of elevation classes, in which the ice surface model is run at multiple elevations within each grid cell, has proven to be a useful way for a low-resolution atmosphere inside a general circulation model (GCM) to produce high-resolution downscaled surface mass balance fields for use in one-way studies coupling atmospheres and ice flow models. Past uses of elevation classes have failed...