Motivated by recent evidence of strong stratospheric–tropospheric coupling during the Northern Hemisphere winter, this study examines the evolution of the atmospheric flow and wave fluxes at levels throughout the stratosphere and troposphere during the composite life cycle of a sudden stratospheric warming. The composite comprises 39 major and minor warming events using 44 years of NCEP–NCAR re...

Phase coherence between geomagnetic activity and temperature vari7 ability from stratosphere to troposphere is quantified and statistically tested in 8 the oscillatory mode with the period 7–8 years using the ERA-40/ERA-Interim 9 and NCEP/NCAR reanalysis monthly air temperature data. Conditional phase 10 coherence is used to identify the North Atlantic Oscillation (NAO) as a mediator 11 transfe...

Abstract The upper boundary height of the traditional community general circulation model ionosphere‐thermosphere system is too low to be applied topside ionosphere/thermosphere study. In this study, National Center for Atmospheric Research Thermosphere‐Ionosphere‐Electrodynamics General Circulation Model (NCAR‐TIEGCM) was successfully extended upward by four scale heights from 400–600 km 700–1...

The Weather Research and Forecasting (WRF) modelling system is developed as a collaborative partnership between the National Center for Atmospheric Research (NCAR), the National Oceanic and Atmospheric Administration (the National Centers for Environmental Prediction (NCEP) and the Forecast Systems Laboratory (FSL)), the Air Force Weather Agency (AFWA), the Naval Research Laboratory, Oklahoma U...

A grand scientific challenge for this century is to understand the complex interrelationships among the atmosphere, ocean, land processes, biosphere and human activities that define the Earth System. Coupled with this effort is the need to predict changes to our environment and to translate such changes into more immediate economic and societal impacts. There is a corresponding challenge for st...

This initiative is composed of three elements, which were chosen based on consideration of recurring themes and issues that have emerged in assessments of the effects of climate variability and change on human society and the environment, and in which there are important research gaps. The two most recent noteworthy assessments have provided considerable material for consideration of the state ...

This paper is a brief overview of a parallel version of the NCAR Community Climate Model, CCM2, implemented for MIMD massively parallel computers using a message-passing programming paradigm. The parallel implementation was developed on an Intel iPSC/860 with 128 processors and on the Intel Delta with 512 processors, and the initial target platform for the production version of the code is the ...

Continuous monitoring of the surface temperature is critical to understanding and forecasting Arctic climate change; as surface temperature integrates changes in the surface energy budget. The sea-ice surface temperature (IST) has been measured with optical and thermal infrared sensors for many years. With the IST Environmental Data Record (EDR) available from the Visible Infrared Imaging Radio...