dc.description.abstract | In recent years, after most of the focus of the world attention on global warming, the Arctic sea ice melting condition has become main research issue for scientists. Sea ice in the Arctic is very sensitivity to climate changes. It can help regulate the amount of incoming and insolation absorbed by the earth and exchanges momentum, heat, and chemical constituents between the atmosphere and the ocean. Therefore, monitoring for the changes of the Arctic sea ice will help us to comprehend the causation of climate change of potential factors. According to researches, the phenomenon of positive ice-albedo feedback and atmospheric precipitable water are important factors to affect climate changes in the Arctic region. Therefore, the main purpose of this study is to analyze how the positive ice-albedo feedback to affect the distribution of precipitable water on the Arctic Polar Cell.
The research data used in this study has been divided into two categories, namely, the Special Sensor Microwave/Imager (SSM/I) microwave radiometer data that is onboard the Defense Meteorological Satellite Program (DMSP) satellite and the NCEP/NCAR reanalysis data. By the observation, sea ice area in the years of 1989 to 1996 was in an oscillatory equilibrium state, while the years of 1997 to 2007 was in a positive ice-albedo feedback state. On analysis that will discuss the relationship between the distribution of precipitation on the Arctic Polar Cell and climatic factors by comprehensive and comparative studying. In this study, we divided the distribution of precipitation on the Arctic Polar Cell into 6 areas in latitude from 60 -90 degrees, and compares the results with previous periods of climatic factors in different geographical and season distribution.
According to the results of the analysis, in the different seasons, when positive ice-albedo feedback is active, both marine and terrestrial area of precipitable water increased significantly in the summer, and regional analysis shows that precipitable water has increased trend at marine in winter by positive ice-albedo feedback effect. However, precipitable water in the Scandinavia and the Rocky Mountains are less than before the period of positive ice-albedo feedback. The possible cause is that the Arctic oscillation system (AO) was in the negative phase at this stage, resulting in cold air southward and taking away atmospheric water vapor. To sum up the previous results, it shows that positive ice-albedo feedback in the Arctic Polar Cell has significant effected upon sea ice area, temperature, precipitable water, and with the impact of climate warming in recent years that is showing dramatic changes, thus, it’s a special issue that worth to observe consistently in the future.
| en_US |