The quasi-geostrophic omega equation has been used extensively to examine the large-scale vertical velocity patterns of atmospheric systems. It is derived from the quasi-geostrophic equations, a balanced set of equations based on the partitioning of the horizontal wind into a geostrophic and an ageostrophic component. Its use is limited to higher latitudes, however, as the geostrophic balance is undefined at the equator. In order to derive an omega equation which can be used at all latitudes, a new balanced set of equations is developed. Three key steps are used in the formulation. First, the horizontal wind is decomposed into a nondivergent and an irrotational component. Second, the Coriolis parameter is assumed to be slowly varying, such that it may be moved in and out of horizontal derivative operators as necessary to simplify the derivation. Finally, the mass field is formulated from the nondivergent wind field. The resulting balanced set of equations and the omega equation derived from them take a similar form to the quasi-geostrophic equations, yet are valid over the whole sphere. A method of solution to the global omega equation using vertical normal modes and spherical harmonics is presented, along with a middle-latitude and low-latitude example.
2017 | Geophysical Research Letters 44(9), 4304-4312, 2017
Description:
Climate models have consistently projected a drying trend in the southwestern United States, aiding speculation of increasing dust storms in this regi...
2017 | Journal of Advances in Modeling Earth Systems 9(2), 1473-1487, 2017
Description:
Numerical solution of the one-dimensional Richards' equation is the recommended method for coupling groundwater to the atmosphere through the vadose z...
2017 | Journal of Geophysical Research: Space Physics 122(8), 9056-9067, 2017
Description:
Since the mid-1970s, the Defense Meteorological Satellite Program (DMSP) spacecraft have operated instruments for monitoring the space environment fro...
2017 | Journal of Geophysical Research: Space Physics 122(8), 9068-9079, 2017
Description:
We have developed a method for reprocessing the multidecadal, multispacecraft Defense Meteorological Satellite Program Special Sensor Magnetometer (DM...
2016 | Journal of Advances in Modeling Earth Systems 8(4), 1969-1985, 2016
Description:
In this study, a one-dimensional (1-D) thermal diffusion lake model within the Weather Research and Forecasting (WRF) model was investigated for the L...
2017 | Geophysical Research Letters 44(9), 4107-4115, 2017
Description:
This study investigates some of the benefits and drawbacks of assimilating terrestrial water storage (TWS) observations from the Gravity Recovery and ...
2016 | Journal of Advances in Modeling Earth Systems 8(2), 719-734, 2016
Description:
Assimilation of satellite radiances has been proven to have positive impacts on the forecast skill, especially for regions with sparse conventional ob...
2018 | Journal of Advances in Modeling Systems 10(2), 421-447, 2018
Description:
Detailed, regional climate projections, particularly for precipitation, are critical for many applications. Accurate precipitation downscaling in the ...
2017 | Earth and Space Science 4(5), 314-334, 2017
Description:
While global climate models (GCMs) provide useful projections of near‐surface wind vectors into the 21st century, resolution is not sufficient enoug...
Estuarine environments are continuously being shaped by both natural and anthropogenic sources which directly/indirectly influence the organisms that ...
2017 | Journal of Advances in Modeling Earth Systems 9(2), 870-892, 2017
Description:
Previous modeling work showed that aerosol can affect the position of the tropical rain belt, i.e., the intertropical convergence zone (ITCZ). Yet it ...
2018 | Journal of Advances in Modeling Systems 10(4), 989-1010, 2018
Description:
Parametric uncertainty in convection parameterization is one major source of model errors that cause model climate drift. Convection parameter tuning ...
2017 | Journal of Advances in Modeling Earth Systems 9(1), 291-306, 2017
Description:
We propose a general methodology for determining the lagged ensemble that minimizes the mean square forecast error. The MSE of a lagged ensemble is sh...
2016 | Journal of Advances in Modeling Earth Systems 8(4), 1552-1564, 2016
Description:
Influences of the diurnal cycle on the propagation of the Madden-Julian Oscillation (MJO) convection across the Maritime Continent (MC) are examined u...
2018 | Journal of Advances in Modeling Systems 10(4), 961-970, 2018
Description:
Precipitation is an important climate quantity that is critically relevant to society. In spite of intense efforts, significant precipitation biases r...
2018 | Journal of Advances in Modeling Systems 10(4), 1074-1086, 2018
Description:
The mean square error (MSE) of a lagged ensemble of monthly forecasts of the Niño 3.4 index from the Climate Forecast System (CFSv2) is examined with...
2019 | Journal of Advances in Modeling Earth Systems 11(6), 1803-1829, 2019
Description:
Strongly coupled data assimilation (SCDA) views the Earth as one unified system. This allows observations to have an instantaneous impact across bound...
2016 | Journal of Advances in Modeling Earth Systems 8(2), 917-935, 2016
Description:
A number of recent studies investigated impacts of Land-Use and Land-Cover Changes (LULCC) on climate with global Earth System Models (ESMs). Yet many...
2016 | Journal of Advances in Modeling Earth Systems 8(4), 1586-1619, 2016
Description:
The collective effects of convection can influence large-scale circulations that, in turn, act to organize convective activity. Such scale interaction...
2020 | J. Appl. Meteor. Climatol. (2020) 59 (6): 1091–1107.
Description:
The Land–Atmosphere Feedback Experiment (LAFE) was a field campaign to investigate influences of different land surface types on the atmospheric bou...
2019 | Geoscientific Model Development, 12(3), 1139-1164
Description:
Polar amplification – the phenomenon where external radiative forcing produces a larger change in surface temperature at high latitudes than the glo...
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