A static polarization interferometer for measuring upper atmospheric winds is presented, based on two Savart plates with their optical axes perpendicular to each other. The principle and characteristics of the interfe...A static polarization interferometer for measuring upper atmospheric winds is presented, based on two Savart plates with their optical axes perpendicular to each other. The principle and characteristics of the interferometer are described. The interferometer with a wide field of view can offer a stable benchmark optical path difference over a specified spectral region of 0.55-0.63μm because there are no quarter wave plates. Since the instrument employs a straight line common-path configuration but without moving parts and slits, it is very compact, simple, inherently robust and has high throughput. The paper is limited to a theoretical analysis.展开更多
The damage and loss of life from fresh water flooding as Tropical Cyclones move inland and towards higher latitudes rivals the losses at the point of landfall. This makes it extremely important to understand the struc...The damage and loss of life from fresh water flooding as Tropical Cyclones move inland and towards higher latitudes rivals the losses at the point of landfall. This makes it extremely important to understand the structure of these systems as some such events produce much less damaging rainfall. Extreme rainfall and major flooding events are studied around the Globe to examine the likely structure of weather systems which produce extreme rainfall. An extensive search for rare radio-sonde data has been carried out near where extreme rainfall and flooding has been reported. In almost every case atmospheric moisture content is high and the low-level wind direction turns anti-cyclonically with increasing height up to 500 h Pa. The rare exception to the rule is when tropical thunderstorms generate extreme rainfall. This study extends previous work in Eastern Australia by showing that the link between turning winds and rainfall exists in both the tropics and temperate zones, and the link applies in cases of extreme rainfall and associated major flooding.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No.40875013)the National Defense Basic Scientific Research Project (Grant No.A1420080187)+1 种基金the National High Technology Research and Development Program of China (Grant No.2006AA12Z152)the State Key Program of National Natural Science Foundation of China (Grant No.40537031)
文摘A static polarization interferometer for measuring upper atmospheric winds is presented, based on two Savart plates with their optical axes perpendicular to each other. The principle and characteristics of the interferometer are described. The interferometer with a wide field of view can offer a stable benchmark optical path difference over a specified spectral region of 0.55-0.63μm because there are no quarter wave plates. Since the instrument employs a straight line common-path configuration but without moving parts and slits, it is very compact, simple, inherently robust and has high throughput. The paper is limited to a theoretical analysis.
文摘The damage and loss of life from fresh water flooding as Tropical Cyclones move inland and towards higher latitudes rivals the losses at the point of landfall. This makes it extremely important to understand the structure of these systems as some such events produce much less damaging rainfall. Extreme rainfall and major flooding events are studied around the Globe to examine the likely structure of weather systems which produce extreme rainfall. An extensive search for rare radio-sonde data has been carried out near where extreme rainfall and flooding has been reported. In almost every case atmospheric moisture content is high and the low-level wind direction turns anti-cyclonically with increasing height up to 500 h Pa. The rare exception to the rule is when tropical thunderstorms generate extreme rainfall. This study extends previous work in Eastern Australia by showing that the link between turning winds and rainfall exists in both the tropics and temperate zones, and the link applies in cases of extreme rainfall and associated major flooding.
