Eddy Correlation Measurments of Snow-Atmosphere Exchange of N0y and Water Vapor at Summit (Greenland)

这是四个协调项目之一，这些项目将利用格陵兰内陆冰盖上建立的营地设施，作为GISP-2冰芯钻探工作的一部分，以调查大气痕量元素是如何沉积在冰上的，以及它们被并入冰中时会经历什么样的变化。为了正确解释可以从冰芯中恢复的替代气候数据，有必要了解这些过程。虽然最近在提取和分析冰芯方面取得了重大进展，但在了解活性化学物质的空气到雪的转移过程方面的进展仍然滞后。该项目的目标是确定活性氮氧化物、水蒸气、显热和动量的垂直通量。通过1994年和1995年的现场测量计划。一个具体目标是确定大气和雪中活性氮氧化物浓度之间的传递函数，从而能够根据大气光化学和氮的生物地球化学循环的变化来解释冰芯中的硝酸盐记录。其他目标是确定调节空气和雪之间活性氮氧化物交换的环境变量，评估DR以及湿沉积和再蒸发在控制硝酸盐积累方面的相对重要性，以及分析控制向冰盖供应硝酸盐的气象条件。

This is one of four coordinated projects that will make use of the camp facilities established on the ice sheet in the interior of Greenland as part of the GISP-2 ice core drilling effort, in order to investigate how atmospheric trace elements are deposited on the ice and what kind of changes they undergo as they are being incorporated into the ice. An understanding of such processes is necessary in order to properly interpret the proxy climate data that can be recovered from ice cores. While significant progress has been made recently in extracting and analyzing ice cores, progress in understanding the air to snow transfer process for reactive chemical species has lagged behind. The goal of this project is to determine the vertical fluxes of reactive nitrogen oxides, water vapor, sensible heat, and momentum. through a field measurement program in 1994 and 1995. A specific objective is to define the transfer function between reactive nitrogen oxide concentrations in the atmosphere and in the snow, thus allowing the interpretation of the nitrate record in ice cores in terms of changes in atmospheric photochemistry and in the biogeochemical cycling of nitrogen. Other objectives are to determine the environmental variables regulating the exchange of reactive nitrogen oxides between air and snow, to assess the relative importance of dr and wet deposition and reevaporation in controlling the nitrate accumulation, and to analyze the meteorological conditions controlling the supply of nitrates to the ice sheet.