Observing the range of spatial scales important in thunderstorm electrification and subsequent lightning development is huge and would be an impossible task. The charge transfer processes within clouds takes place during collisions of particles with diameters on the order of 10-1000 $\mu$m, whereas the distance between the ...

This study focuses on the air-sea interactions over the northern oceans from an observational point of view. Atmosphere-ocean interactions exhibit a strong seasonality in both the North Pacific and the North Atlantic. In winter, the atmospheric forcing of the ocean through modulating the latent and sensible heat fluxes is the ...

The transition from the subtropical stratocumulus-capped marine boundary layer to the trade-cumulus boundary layer is studied using numerical simulations. Model results are used to propose a new conceptual model of this transition based on the decoupling of turbulent convective eddies near the sea surface from those within ...

The dominant spatial patterns of climatic fluctuation over the contiguous United States during the winter and summer seasons (1931-82) are examined using monthly mean temperature and monthly total precipitation anomalies for the 344 climatic divisions. These data are expanded into orthogonal components using rotated principal ...

A full-Galerkin GCM is developed for mechanistic studies on the generation mechanisms of low-frequency variability. The numerical implementation and baroclinic dynamics of this newly developed GCM are carefully tested, and its sensitivity to vertical resolution and to parameterized physics are also investigated.The role of ...

Observational analyses and numerical simulations are used to investigate the interaction between frontal systems and the complex terrain of the western U.S. for both warm and cold seasons. The different characteristics of mesoscale phenomena resulting from the interaction for each synoptic condition are explored and compared.For ...

The exchange of mass and chemical constituents between the stratosphere and the troposphere is examined on a variety of time scales using various techniques. Estimates are developed of the stratosphere-troposphere exchange of important chemical species, and commercial aircraft emissions. Various methods for stratosphere-troposphere ...

Large-scale interannual and interdecadal variability in surface-observed marine stratiform cloud (MSC) amount and sea surface temperature (SST) are closely coupled over the central North Pacific during summer. Increased (decreased) MSC amount occurs with decreased (increased) SST, resulting from coincident meridional shifts ...

Coarse resolution models are used to investigate the influence of Southern Hemisphere processes on the Northern branch of the thermohaline circulation. The link between the zonal wind stress at the latitude of Drake Passage and the production of deep water in the Northern Hemisphere is explored. A nearly linear response to ...

The low frequency variability in the equatorial middle atmosphere is dominated by the semiannual (SAO) and quasi-biennial (QBO) oscillations. Although the general characteristics and forcing mechanisms of these oscillations are thought to be known, these oscillations are still not well reproduced in modeling experiments of ...