Maeng-Ki Kim

Department of Atmospheric Science
Kongju National University
182, Shinkwan-dong, Kongju
Chungnam, 314-701, Korea
Tel:+82 0416 50 8531
Fax:+82 0416 856 5871
E-mail: mkkim@climate.kongju.ac.kr


Education and Professional Career

Dissertation Research

ABSTRACT

In this study, Global and Korean warming are investigated using the observed data for last 40 years, and the dynamics of global warming associated with land surface processes are investigated using GCM. The scenario method is developed and applied to predict the regional climate from GCM large-scale predictors.

The global circulation patterns associated with global warming and those associated with Korean regional warming are identified using a canonical correlation method. The two circulation patterns obtained are very similar to each other, indicating the Korean warming for past 40 years is strongly associated with global warming. The associated spatial pattern of global surface air temperature is characterized by the strong temperature increase in land and the weak decrease in ocean except the tropical ocean. This global warming pattern is associated with the sea level pressure pattern characterized by the decrease in the high latitudes and the increase in the middle latitudes.

The scenario method is developed based on the coupled mode between GCM large-scale predictors and regional climate variables. The methodology utilized is the canonical correlation method developed by combining the EOF and SVD methods. The Korean warming scenarios are obtained by applying this method to the the data obtained from long-term simulations of GFDL coupled ocean-atmosphere model and a long-term observaion data in Korea. The urbanization effects over city stations in Korean peninsula are deduced by identifying an urbanization mode obtained from EOF analysis of station temperature. The Korean mean temperature occurred for past 40 years is found to be about 0.64C, but the regional warming associated with global warming is about 0.28C after removing the urban warming (0.36C). Using climate sensitivity parameter in various GCMs which was suggested by Cess et al. (1989), uncertainty of Korean warming due to the CO2 doubling is estimated. Estimated value for Korean warming is about 2.2C with uncertainty of 1.3C, similar to global warming of about 2.4C which was suggested by IPCC (1990).

The dynamics associated with global warming are investgated using two sets of 10 year GCM simulations with 1xCO2 and 2xCO2 atmospheric concentrations. Surface warming due to the CO2 doubling is more stronger in the northern part than in the middle part of the continent of Asia. Cloud changes in the northern Asia are characterized by the increase of high level cloud during all season and strong decrease of middle and low level cloud during spring and summer season. Surface warming is enhanced due to the increase of downward longwave radiation by the increase of high level cloud. especially in fall and winter season. But, in late spring and early summer, surface warming by the increase of shortwave radiation is mainly due to the decrease of surface albedo by an early melting of snow and early termination of snowmelt. it is found that the hydrological cycle is more enhanced by the CO2 doubling, particularly over the high latitudes in the northern hemisphere. Enhanced surface evaporation by surface warming over the high latitude continental region plays an important role in maintaining the enhanced hydrological cycle which makes high level cloud to be increased, especially in spring and summer season. But, in fall and winter season, evaporation from the ocean surface upstream plays an important role in maintaining the enhanced hydrological cycle.