Gottwald / Bovensmann SCIAMACHY - Exploring the Changing Earth's Atmosphere

1. Auflage 2010
ISBN: 978-90-481-9896-2
Verlag: Springer Netherlands
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, 225 Seiten

SCIAMACHY, the SCanning Imaging Absorption spectroMeter for Atmospheric CHar­tographY, is a passive sensor for exploring the Earth's atmosphere. It is part of the payload of the European Earth Observation mission ENVISAT, launched on 1 March 2002. SCIAMACHY observes absorption spectra of molecules from the UV (214 nm) to the short-wave infrared wavelength range (2386 nm) and derives the atmospheric composition - trace gases, aerosols, clouds - from these measurements. Having meanwhile successfully monitored and explored the Earth's atmosphere for more than 8 years, new and exciting insights into the Earth-atmosphere system are obtained. The provided global data sets do not only cover greenhouse gases and pollutants in the troposphere or the ozone chemistry in the stratosphere but even reach up to the mesosphere and lower thermosphere. They contribute significantly to atmospheric physics and chemistry as well as climate change research.SCIAMACHY is one of the major current Earth Observation undertakings of Germany, The Netherlands and Belgium, accomplished in cooperation with the European Space Agency (ESA). Many scientific groups at various institutes in Europe and abroad were and are actively involved in the analysis of the data.This book is a comprehensive summary describing the entire SCIAMACHY mission - from the very first ideas to the current results. It illustrates how the measurements are performed, how the trace gas concentrations are derived from the measured spectra and how the unique data sets are used to improve our understanding of the changing Earth's atmosphere. The targeted readership is not only the existing and potentially new SCIAMACHY data users from undergraduate student level up to researchers new in the fields of atmospheric chemistry and remote sensing, but anyone who is keen to learn about SCIAMACHY's efforts to study the atmosphere and its responses to both, natural phenomena and anthropogenic effects.

Autoren/Hrsg.

Bovensmann, Heinrich

Gottwald, Manfred

Inhaltsverzeichnis

1;Editorial;8
2;Contents;12
3;Contributors;14
4;Chapter 1: SCIAMACHY - The Need for Atmospheric Research from Space;18
4.1;1.1How to Study the Earth´s Atmosphere from Space?;19
4.2;1.2The Road to SCIAMACHY;20
4.3;1.3Determining Impacts on the Earth´s Atmosphere;23
4.3.1;SCIAMACHY´s Goals;23
4.3.2;The Atmospheric Layers;24
4.3.3;Anthropogenic Impact on the Earth-Atmosphere System;26
4.3.4;Tropospheric Chemistry;26
4.3.5;Greenhouse Gases: Global Warming and Climate Change;27
4.3.6;The Tropopause Region;29
4.3.7;Stratospheric Chemistry and Dynamics;29
4.3.8;Mesospheric Chemistry and Dynamics;30
4.4;1.4SCIAMACHY´s Past and Beyond Its Future;31
4.4.1;The Initial Phases;31
4.4.2;The Next Decades;32
4.5;References;33
5;Chapter 2: ENVISAT - SCIAMACHY´s Host;35
5.1;2.1ENVISAT Attitude and Orbit;36
5.2;2.2ENVISAT On-board Resources;39
5.3;2.3ENVISAT Ground Segment;40
5.4;2.4ENVISAT Data Products;40
5.5;2.5Data Access;43
5.6;References;44
6;Chapter 3: The Instrument;45
6.1;3.1Instrument Concept;46
6.2;3.2Optical Assembly;48
6.2.1;Scan Mechanisms and Baffles;48
6.2.2;Telescope and Spectrometer;51
6.2.3;Detector Modules;51
6.2.4;Calibration Unit;55
6.2.5;Polarisation Measurement Device;55
6.2.6;Radiator A and Active Thermal Control;56
6.2.7;Thermal Bus;57
6.3;3.3Radiant Cooler Assembly;57
6.4;3.4Electronic Assembly;58
6.4.1;Instrument Control Unit;58
6.4.2;Secondary Processors;59
6.4.3;Modes;59
6.5;3.5The Making of SCIAMACHY;59
6.6;References;62
7;Chapter 4: Instrument Operations;63
7.1;4.1Sun and Moon Observation;64
7.1.1;Sun Occultation;66
7.1.2;Sub-solar Observations;66
7.1.3;Moon Occultation;67
7.1.4;Refraction;68
7.2;4.2Reference Measurement Orbit;68
7.3;4.3Mission Scenarios;69
7.4;4.4Parameter Tables;70
7.5;4.5Measurement States;71
7.5.1;State Definition;71
7.5.2;Nadir and Limb States;72
7.5.3;Occultation States;74
7.5.4;Calibration and Monitoring States;74
7.6;4.6Timelines;75
7.6.1;Timeline Concept;75
7.6.2;Timeline Definition;76
7.7;4.7SCIAMACHY Operations Setup;76
7.8;References;78
8;Chapter 5: Calibration and Monitoring;79
8.1;5.1On-ground Calibration Philosophy;79
8.2;5.2The General Calibration Equation;80
8.3;5.3Detector Corrections;81
8.3.1;Channels 1-5 (UV-VIS-NIR);82
8.3.2;Channels 6-8 (SWIR);84
8.4;5.4Wavelength Calibration;84
8.5;5.5Stray Light;85
8.5.1;Spectral Stray Light;85
8.5.2;Spatial Stray Light;86
8.6;5.6Polarisation;86
8.7;5.7Radiometric Calibration;89
8.8;5.8Optical Performance Monitoring;90
8.9;References;91
9;Chapter 6: SCIAMACHY In-Orbit Operations and Performance;92
9.1;6.1 Commissioning Phase;92
9.1.1;Engineering Tasks;93
9.1.2;Measurement Tasks;94
9.1.3;The SODAP Sequence;94
9.1.4;The Validation Sequence;95
9.2;6.2 Routine Operations Phase;95
9.2.1;Operation Change Requests and Final Flight Configuration;97
9.3;6.3 Optical Performance;98
9.3.1;Optical Throughput;98
9.3.2;Scan Angle Dependence;100
9.3.3;Light Leak in Channel 7;101
9.3.4;Spatial Stray Light in Limb Measurements;102
9.4;6.4 Thermal Performance;103
9.4.1;Ice on Detectors 7 and 8;103
9.4.2;Decontamination;103
9.4.3;Active Thermal Control;104
9.4.4;Thermal Control;105
9.5;6.5 Line-of-Sight Performance;108
9.5.1;Scanners;108
9.5.2;Extra Mispointing;109
9.5.3;Tangent Height;109
9.6;6.6 Mission Extension;110
9.6.1;Orbit Modification;110
9.6.2;Impact on Instrument Performance;112
9.7;References;112
10;Chapter 7: From Radiation Fields to Atmospheric Concentrations - Retrieval of Geophysical Parameters;113
10.1;7.1 Radiative Transfer in the Earth´s Atmosphere;114
10.2;7.2 Nadir Trace Gas Retrieval Schemes;116
10.2.1;DOAS Retrieval;116
10.2.2;Modified DOAS Methods;121
10.3;7.3 Cloud and Aerosol Retrieval;121
10.3.1;Cloud Parameters;122
10.3.2;Cloud Fraction (CF);123
10.3.3;Cloud Top Height (CTH);125
10.3.4;Cloud Geometrical Thickness (CGT);125
10.3.5;Cloud Optical Thickness (COT) and Effective Radius (Reff,cld);125
10.3.6;Cloud Phase Index (CPI);126
10.3.7;Tropospheric Aerosol Parameters;126
10.4;7.4Surface Parameter Retrieval;127
10.4.1;Surface Albedo;127
10.4.2;Land Vegetation;129
10.4.3;Oceanic Biological Activity;129
10.5;7.5Inversion Theory;129
10.6;7.6Application of Inversion Theory to Limb Retrieval;131
10.7;7.7 Derivation of Tropospheric Information;133
10.7.1;Reference Sector Method;134
10.7.2;Limb/Nadir Matching;134
10.7.3;Data Assimilation - The NO2 Example;137
10.8;References;137
11;Chapter 8: Data Processing and Products;142
11.1;8.1Operational Processing Overview;143
11.1.1;Level 1b Product;143
11.1.2;Level 1c Product;144
11.1.3;Level 2 Product;144
11.1.4;Processing Chains;144
11.2;8.2Operational Level 0-1b Processing;146
11.2.1;Memory Effect and Non-linearity;146
11.2.2;Dark Signal;146
11.2.3;Pixel-to-Pixel Gain and Etalon;148
11.2.4;Dead and Bad Pixel Mask;149
11.2.5;Spectral Stray Light;149
11.2.6;Wavelength Calibration;150
11.2.7;Polarisation;151
11.2.8;Radiometric Correction;151
11.2.9;Sun Mean Reference Spectrum;152
11.2.10;Degradation;152
11.3;8.3Operational Level 1b-2 Data Processing;152
11.3.1;Column Densities from Nadir Observations;152
11.3.2;Cloud and Aerosol Parameters in the UV-VIS-NIR for Nadir Observations;153
11.3.3;Profiles from Limb Observations;153
11.3.4;Limb Cloud Detection;156
11.4;8.4Scientific and Value-Added Products;156
11.4.1;Scientific Products;156
11.4.2;Value-Added Products;156
11.5;References;158
12;Chapter 9: Validation;159
12.1;9.1Validation Strategy;160
12.1.1;Validation Principles;160
12.1.2;Comparison Errors and Representativeness;161
12.2;9.2Validation Organisation;162
12.2.1;ESA Validation Structure;162
12.2.2;SCIAVALIG Structure;163
12.3;9.3Correlative Measurements;164
12.3.1;Ground-Based Instruments;164
12.3.2;Shipborne Campaigns;167
12.3.3;Airborne Campaigns;167
12.3.4;Balloon-Borne Campaigns;170
12.3.5;Satellite Intercomparisons;171
12.4;9.4 Validation Results;172
12.4.1;Level 1 Irradiance and Reflectance UV-VIS-NIR-SWIR;173
12.4.2;Level 2 Products from Nadir UV-VIS-NIR;174
12.4.3;Level 2 Products from Nadir SWIR;176
12.4.4;Level 2 Products from Limb UV-VIS;178
12.5;References;183
13;Chapter 10: SCIAMACHY´s View of the Changing Earth´s Environment;186
13.1;10.1Tropospheric Composition - Greenhouse Gases;187
13.1.1;Carbon Dioxide - CO2;187
13.1.2;Methane - CH4;187
13.1.3;Water Vapour - H2O;188
13.1.4;Heavy Water - HDO;189
13.1.5;Absorbing Aerosol Index and Precipitation;189
13.2;10.2Tropospheric Composition - Reactive Gases;192
13.2.1;Nitrogen Dioxide - NO2;192
13.2.2;Sulphur Dioxide - SO2;196
13.2.3;Formaldehyde (HCHO) and Glyoxal (CHOCHO);196
13.2.4;Carbon Monoxide - CO;198
13.2.5;Tropospheric Halogen Oxides - BrO and IO;200
13.3;10.3The Stratospheric Ozone Layer;202
13.3.1;Ozone - O3;203
13.3.2;Chlorine Dioxide - OClO;208
13.3.3;Bromine Oxide - BrO;210
13.3.4;Polar Stratospheric Clouds - PSC;211
13.4;10.4The Upper Atmosphere and Solar Activity;211
13.4.1;Noctilucent Clouds - NLC;212
13.4.2;Mesospheric Ozone and the October/November 2003 Solar Storm;214
13.4.3;Mesopause Temperatures, Thermospheric NO and Metal Layers;215
13.4.4;Observing the Active Sun - The Mg II Index;218
13.5;10.5The Earth Surface and Beneath;220
13.5.1;Land Vegetation Characteristics;220
13.5.2;Oligotrophic Oceanic Regions;221
13.5.3;Oceanic Phytoplankton Characteristics;221
13.6;10.6SCIAMACHY and the Goddess of Love;221
13.7;References;224
14;Appendix;228
14.1;Atmospheric Gases;228
14.2;Abbreviations and Acronyms;228
15;Index;234