I. Remote spectroscopic measurements of atmospheric deuterated water/water and column carbon dioxide. II. Interannual variations of the Earth's reflectance.

摘要

The theme of this thesis is to apply remote sensing data on problems concerning the climate system.; In Chapter 1, we derive the first simultaneous measurements of HDO and H₂O in the tropical upper troposphere and lower stratosphere using the Atlas-3 Atmospheric Trace Molecule Spectroscopy (ATMOS) data. The derived HDO/H₂O ratio demonstrates that convection has a major influence on the moisture budget and the dehydration processes in this region.; In Chapter 2, we introduce a method of measuring column averaged CO ₂ volume mixing ratio (VMR) with high-resolution spectrometry of reflected sun light at the CO₂ (1.58-μm and 2.06-μm) and O₂ (0.76-μm) bands. Using prototype retrieval simulations based on a practical satellite instrument design, we show that this approach has the potential for highly accurate column CO₂ VMR measurements.; In Chapters 3–5, we examine the interannual variations in the Earth s reflectance using the Nimbus-7 Total Ozone Mapping Spectrometer (TOMS) reflectance measurements. Chapter 3 introduces the TOMS measurements and provides an overview on the interannual variability of the Earth's reflectance. Variations in the globally averaged reflectance are also used to examine a postulated cosmic ray-cloud-climate connection. In Chapter 4, we relate interannual reflectance variations over the summertime polar icy areas to variations in the microwave-derived sea ice concentration. An interesting hemispheric asymmetry is found: a unit change in the sea ice concentration is related to a significantly larger reflectance change in the Antarctic than in the Arctic icy areas. Chapter 5 is devoted to interannual reflectance variations over the northern midlatitude oceans. We find that interannual reflectance variations in these regions are, to a large extent, related to variations in the large-scale circulation, mostly through variations in the storm tracks. The findings in this chapter suggest that the response of clouds to climate change may be better viewed from a large-scale circulation perspective, other than a purely thermodynamic one (such as in the cloud-temperature relations), a stand many previous investigations have taken.