Studies on the Water Vapor Transportation, Precipitation and Atmospheric Disturbances over the Norwegian Sea Regions Affecting the Climate in the Northern Hemisphere

众所周知，挪威海地区对于了解北半球的能量和水汽转化非常重要，因为挪威海在仲冬季节不会冻结。因此，斜压区是在起源于中纬度地区的暖气团和起源于高纬度地区的冷气团之间形成的。在这种条件下，该带周围频繁地产生极低压。为了研究大气扰动的结构、活动和降水现象，在挪威Bear Island （Bjornoya）气象台（74°30′n, 19°01′e）设置了北海道大学科学研究生院的x波段垂直指向多普勒雷达。从2001年9月至2004年8月，连续进行了三年的观测。该地区的雷达观测是迄今为止的第一次。为了估算降水强度的空间分布，进一步研究了雷达反射率(Z)与降水强度(R)、降水强度(R)与降水粒子下落速度（V_p）的关系。从而澄清了挪威海地区降水强度和含水量的实际情况。此外，对日本国家极地研究所在挪威斯瓦尔巴群岛的Ny-Alesund站（78°55′n, 20°25′e）的雷达资料进行了分析。结果表明，雷达回波在高度方面呈现出明显的季节变化，并明确为四种模式。在芬兰Sodankyla的北极研究中心，对雪晶和气溶胶颗粒进行了四个冬季的观测，并获得了一些有趣的结果。研究了北极地区积雪厚度的致密化现象和压缩粘度，并与温带地区进行了比较。少

It is well known that the Norwegian Sea region is very important to understand the energy and water vapor transformation in the northern hemisphere because the Norwegian Sea does not freeze in the midwinter seasons. Therefore, the baroclinic zone is formed among a warm air-mass which is originated in the mid-latitude and a cold air-mass which is originated in a high latitude region. Under such conditions, the polar lows are generated around the zone frequently. To investigate the structures, activity and precipitation phenomena of the atmospheric disturbances, the X-band vertically pointing Doppler radar of the Graduate School of Science, Hokkaido University was set up at the Bear Island (Bjornoya) Weather Observatory in Norway (74°30′N, 19°01′E). Continuous observations had been conducted through three years from September 2001 to August 2004. The radar observations in this region is the first time till the present.To estimate the spatial distribution of precipitation intensity from t … More he radar data obtained, the relationship between radar reflectivity (Z) and precipitation intensity (R), and precipitation intensity (R) and falling velocity of precipitation particles (V_p) were investigated. As a result, the actual circumstances of the precipitation intensity and water contents over the Norwegian Sea region were clarified.Furthermore, the radar data which was obtained at Ny-Alesund station (78°55′N, 20°25′E) in the Svalbard, Norway, of National Institute of Polar Research of Japan, was analyzed. As a result, the radar echoes showed distinct seasonal variations with respect to height, and clarified into four patterns.The observations of snow crystals and aerosol particles were conducted through four winter seasons at the Arctic Research Center, Sodankyla, Finland, and a number of interesting results were obtained.The densification phenomena and compressive viscosity of the depth of snow cover at the Arctic regions were investigated and compared with the temperate regions. Less