New Horizons in Occultation Research (eBook)

Preface 5
Contents 7
Contributors 10
Part I GNSS Occultation: Methodology,Analysis, and Applications 15
GPS Radio Occultation with CHAMP, GRACE-A, SAC-C, TerraSAR-X, and FORMOSAT-3 /COSMIC: Brief Review of Results from GFZ 16
1 Introduction 16
2 Status of Radio Occultation with CHAMP and GRACE 17
3 Data Analysis and Validation 18
3.1 Vertical Profiling of the Neutral Atmosphere 18
3.2 Ionosphere Profiling: Initial Results 19
3.3 Water Vapor Comparison with MOZAIC 20
3.4 Near-Real Time Data Processing 21
4 Selected RO Application: Global Gravity Wave Characteristics 22
5 GPS Radio Occultation with TerraSAR-X 24
6 Conclusions and Outlook 25
References 26
Error Estimate of Bending Angles in the Presence of Strong Horizontal Gradients 29
1 Introduction 29
2 Ray Manifold and its Description in the Phase Space 30
3 Radio Holographic Error Estimation 33
4 Numerical Simulations 34
5 Conclusions 37
References 37
Phase Transform Algorithm for Radio Occultation Data Processing 39
1 Introduction 39
2 The GRAS Instrument and Signal Regeneration 39
3 The Phase Transform Algorithm 43
4 Derivation of the Phase Transform Algorithm 44
References 49
Using Airborne GNSS Receivers to Detect Atmospheric Turbulence 50
1 Introduction 50
2 TheoryWeak Scattering 51
3 Results 52
3.1 Log-Amplitude Spectra: Analytic Forms 52
3.2 Simulation Studies and Parameter Estimation 53
3.3 Iterative Parameter Estimation 56
4 Conclusions and Outlook 57
References 58
The GRAS SAF Radio Occultation Processing Intercomparison Project ROPIC 60
1 Introduction 60
2 Data Set 62
3 Baseline of the Comparison 64
4 Results 66
5 Conclusion 69
References 70
Radio Occultation Soundings in Ionosphere and Space Weather Applications: Achievements and Prospects 73
1 Introduction 73
2 History of Ionospheric RO Soundings 74
3 Achievements 75
3.1 Ionospheric RO Science 76
3.2 Operational Services 79
4 Prospects for the Future 81
5 Conclusions 83
References 84
Part II Solar, Lunar, and Stellar Occultation for Atmospheric Studies 87
SCIAMACHY Solar Occultation: Ozone and NO 2 Profiles 200202007 88
1 Introduction 88
2 Retrieval Scheme 90
3 Validation with the Satellite Instruments HALOE and SAGE II 91
4 Ozone and NO 2 Profiles 20022006 92
5 Conclusions 94
References 94
Retrieval of Trace Gas Concentrations from Lunar Occultation Measurements with SCIAMACHY on ENVISAT 96
1 Introduction 96
2 Retrieval Methodology 98
3 Retrieval Results 99
4 Validation Results 102
5 Summary and Conclusions 104
References 104
Validation of GOMOS/Envisat High-Resolution Temperature Profiles (HRTP) Using Spectral Analysis 106
1 HRTP: Measurement Principle and Retrievals 106
2 Using Spectral Analysis for HRTP Validation: Motivation 108
3 Validation Results 110
3.1 Data Selection 110
3.2 Results of Spectra Comparison 111
4 Conclusions and Outlook 114
References 115
Part III GNSS Occultationfor Atmospheric Studies 117
Assimilation of Radio Occultation Data in the Global Meteorological Model GME of the German Weather Service 118
1 Data Assimilation at the DWD 118
2 Evaluation of Bending Angle Forward Operators 120
3 Monitoring 125
4 Assimilation Experiments 133
5 Conclusions 134
References 135
Sampling of the Diurnal Tide of Temperature Using Formosat-3/ COSMIC Data 137
1 Introduction 137
2 Local Time Sampling Using Formosat-3/COSMIC 138
3 Determination of the Diurnal Tide 141
4 Results and Discussion 142
5 Summary and Conclusions 145
References 145
Recent Advances in the Study of Stratospheric Wave Activity Using COSMIC and CHAMP GPS-RO 147
1 Introduction 147
2 COSMIC 148
2.1 Data Analysis Method 148
2.2 Tropics 150
2.3 Northern Hemisphere Winter 152
3 Champ 152
3.1 Tropics 152
3.2 Polar Regions 153
4 Future Directions 155
References 155
Recent Advances in Gravity Wave Analysis from Long Term Global GPS Radio Occultation Observations 158
1 Introduction 158
2 GPS-RO Capabilities 159
3 Case Studies: Two WA Events over Andes 161
3.1 Specific Features of GW Generation and Propagation 161
3.2 Mesoscale Numerical Simulation and GWs Analysis 162
3.3 Comparison of Observed and Simulated GW Activity 166
4 Conclusions 168
References 168
New Applications and Advances of the GPS Radio Occultation Technology as Recovered by Analysis of the FORMOSAT-3/COSMIC and CHAMP Data-Base 170
1 Introduction 170
2 Radio Occultation Method 171
3 Connection Between the Phase Acceleration and Intensity Variations: Experimental Validation 176
4 Wave-Breaking Effect and Determination of Internal Wave Parameters 178
5 Integral Behavior of Wave Activity in the Years 20012003 179
6 Conclusion 180
References 182
Part IV GNSS Occultation for Climate Studies 184
Climatologies Based on Radio Occultation Data from CHAMP and Formosat-3/COSMIC 185
1 Introduction 185
2 Context 187
3 Data and Method 188
4 Results and Discussion 190
4.1 Comparison with ECMWF Analyses 190
4.2 Consistency of Data from Different Satellites 192
5 Concluding Remarks 195
References 196
Testing Climate Models Using Infrared Spectra and GNSS Radio Occultation 199
1 Introduction 199
2 Radiative Feedbacks 200
3 Testing Feedbacks with CLARREO 202
4 Discussion 208
References 209
Construction of Consistent Temperature Records in the Lower Stratosphere Using Global Positioning System Radio Occultation Data and Microwave Sounding Measurements 211
1 Introduction 211
2 COSMIC-AMSU and AMSU-AMSU Calibration Methods 213
3 Results 214
3.1 Using COSMIC Data to Identify AMSU Biases Over Different Orbits and Locations 214
3.2 Using the Calibrated AMSU Data to Calibrate Other Overlapped AMSU Measurements 217
4 Conclusions and Future Work 219
References 220
Lower Stratospheric Temperatures from CHAMP RO Compared to MSU/AMSU Records: An Analysis of Error Sources 222
1 Introduction 222
2 Data 223
2.1 GPS RO Temperature Climatologies 224
2.2 ECMWF Analyses 225
2.3 MSU/AMSU Brightness Temperatures 225
2.4 HadAT2 Radiosonde Data 225
3 Method 226
3.1 Synthetic MSU Temperatures Using Weighting Functions 227
3.2 Synthetic MSU Temperatures Using RTTOVS_8.5 228
4 Results and Discussion 228
4.1 Comparison of TLS Temperatures 228
4.2 Discussion of Error Contributions to RO TLS Data 232
5 Summary, Conclusions, and Outlook 234
References 235
SimVis: An Interactive Visual Field Exploration Tool Applied to Climate Research 238
1 Introduction 238
2 Data 239
3 Method 240
3.1 SimVis -- The Simulation Visualization Tool 240
3.1.1 Feature-Based Visualization and Brushing 240
3.1.2 Linked Views 241
3.1.3 Focus+Context Visualization, 3D View 241
3.1.4 Derived Data 241
3.1.5 Types of Views 242
3.2 SimVis Application to Climate Data 242
4 Results 243
5 Conclusions and Outlook 247
References 247
Trend Indicators of Atmospheric Climate Change Based on Global Climate Model Scenarios 249
1 Introduction 249
2 Data 250
3 Method 251
4 Results 253
5 Discussion with Respect to RO 256
6 Summary and Conclusions 258
References 259
Part V Future Occultation Missions 262
ROSA 0 The Italian Radio Occultation Mission Onboard the Indian OCEANSAT-2 Satellite 263
1 Introduction 263
2 The ROSA Receiver 264
3 Software Development 267
4 Scientific Activities 269
4.1 Space Geodesy 269
4.2 Climate 270
4.3 Space Weather 271
5 Conclusions and Remarks 272
References 273
Radio Occultation Mission in Korea Multi-Purpose SatelliteKOMPSAT-5 274
1 Introduction 274
2 KOMPSAT-5 274
3 AOPOD System 275
3.1 IGOR Receiver and GPS Antennas 275
3.2 Laser Retro Reflector Array 278
4 Occultation Characteristics 279
4.1 Mission Orbit 279
4.2 Occultation Characteristics 279
5 Occultation Data Processing System 279
6 Summary and Conclusions 281
References 282
The Contribution of PROBA2-LYRA Occultations to Earth Atmosphere Composition Analysis 283
1 Introduction 283
2 Forward Model of the Atmosphere Transmittance 284
3 Retrieval Process 287
4 Results 288
5 Conclusion 290
References 290
The Active Temperature, Ozone and Moisture Microwave Spectrometer (ATOMMS) 292
1 Introduction 292
2 High Altitude Initialization of the Hydrostatic and Abel Integrals 294
2.1 Constraining the Abel Bending Angle Integral 295
2.2 Hydrostatic Integral Constraint 296
3 Assessing the Impact of Turbulence on ATOMMS Observations and Retrievals 297
3.1 Simulation Results for Variations in the Refractive Index 298
3.2 Determining the Wet Refractive Index Structure Parameter, C 2 -5pt nw 300
3.3 Comparison with Turbulence Estimates of Gorbunov and Kirchengast (2007) 302
4 Simulated Retrieval Errors (Clear Sky) 303
5 An Approach for Retrievals in the Presence of Inhomogeneous Liquid Water Clouds 304
6 ATOMMS Aircraft to Aircraft Occultation Demonstration 307
References 309
Author Index 311