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A Radiation Coursebased upon Numerical Methods
Björn-Martin Sinnhuber & Stefan Bühler
University of Bremen
Summer semester 2005
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Björn-Martin Sinnhuber
NW1 - W3190
Stefan Bühler
NW1 - N3371
Contact
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Aim and Scope of the Course
The aim of the course is to:
• understand the processes and
• learn how to calculate the transfer of radiation in the
atmosphere.
Main applications of atmospheric radiative transfer are:
• Impact of radiation on climate
• Atmospheric remote sensing
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Organisation of the Course
The course will consist of:• About 7 introductory lectures• About 7 practical exercises at the computers
For the Diploma students:
Kriterium um einen Schein über„erfolgreiche Teilnahme“ zu bekommen:
• Aktive Teilnahme an den praktischen Übungen(höchstens zweimal fehlen)
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Outline of the Next Few Weeks
1. Introduction
2. Radiative Transfer, Part 1
3. Spectroscopy
4. Radiative Transfer, Part 2
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Introduction
• What are numerical methods?
• Why use numerical methods?
• How does this look like in practise?
7SZA = 87.0°
8SZA = 89.5°
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1.0 Blackbody Radiation
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1.1 Planetary Equilibrium Temperature
• Heating by absorption of (shortwave) solar radiation
• Cooling by emission of (longwave) terrestrial radiation
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1.1 Planetary Equilibrium Temperature
• Incoming solar radiation needs to be balanced by outgoing terrestrial radiation.
• Solar constant at top of Earth‘s atmosphere:1376 W m-2
• Outgoing longwave radiation:42
Earth4 Tr
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1.2 A Simple Model of the Greenhouse Effect
Assumptions:
• Single layer atmosphere
with constant temperature
• Atmosphere is transparent
for shortwave solar
radiation
• Atmosphere is a blackbody
for longwave radiation
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1.3 Outgoing Longwave Radiation