Joint Seminar: NUMERICAL MODELING OF MULTISCALE ATMOSPHERIC FLOWS: FROM CLOUD MICROSCALE TO CLIMATE

NUMERICAL MODELING OF MULTISCALE ATMOSPHERIC FLOWS:
FROM CLOUD MICROSCALE TO CLIMATE

Wojciech W. Grabowski

National Center for Atmospheric Research
Boulder, Colorado, USA

An outstanding feature of atmospheric flows is the range of spatial
and temporal scales involved. Development of rain through gravitational
collisions of small cloud droplets concerns processes at sub-centimeter
scales. Size distribution of cloud droplets within turbulent cumulus
and stratocumulus clouds in the tropics and subtropics, where the solar
insolation is at its peak, significantly affects the amount of solar
radiation reflected back to space, and thus the planetary albedo. Tropical
deep convective clouds, often organized into mesoscale convective
systems with horizontal scales of tens to hundreds of kilometers, drive
planetary-scale Hadley circulation, which plays an important role in Earth
energy and water cycles. For all these scales, numerical modeling---either
for scientific research or for practical purposes, like the numerical
weather prediction---plays an important role. The multiscale nature
of these flows, often involving variable physics (e.g., hydrostatic
large-scale flow and nonhydrostatic convective dynamics for the climate
problem) needs to be carefully addressed. In this lecture, I will
present examples of multiscale modeling approaches to selected problems
in atmospheric fluid dynamics. These will include collision/coalescence
of cloud droplets, turbulent entrainment into convective clouds, and
representation of cloud processes in climate models.

Datum

20.05.2009

Uhrzeit

13:30 Uhr

Ort

Bundesstr. 53, room 022/023
Seminar Room 022/023, Ground Floor, Bundesstrasse 53, 20146 Hamburg, Hamburg

ReferentIn

Chair


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