• Ocean and Polar Research
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• 제34권3호
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• pp.305-323
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• 2012

The ocean's response to the Pinatubo and 1259 volcanic eruptions was investigated using an ocean general circulation model equipped with an energy balance model. Volcanic eruptions release gases into the atmosphere which increases the aerosol optical depth and acts to reduce the incoming short-wave radiation. For example, there was a huge volcanic eruption (Pinatubo) in 1991 which reduced the global mean radiative forcing by about 3 W $m^{-2}$. Two numerical experiments were simulated. The first experiment features the Pinatubo eruption and the second experiment simulates the much larger volcanic eruption that occurred in 1259 when the radiative forcing was reduced by 7 times compared to the Pinatubo event. With the reduced radiative forcing due to the Pinatubo eruption at about 3 W $m^{-2}$ and 1259 eruption at about 21 W $m^{-2}$, the global mean sea surface temperature (SST) decreased to its lowest in the second year after each event by about $0.4^{\circ}C$ and $1.6^{\circ}C$, respectively. Sea surface salinity (SSS) increased substantially in the northern North Pacific, northern North Atlantic, and the Southern Ocean. The reduced SST together with SSS increased ocean convection, which yielded an increase in North Atlantic Deep Water, Antarctic Bottom Water, and North Pacific Intermediate Water production and their outflows. The increase in overturning circulation eventually increased the pole-ward ocean heat fluxes. In conclusion, huge volcanic eruptions perturb the ocean substantially and their hallmarks last for more than a decade, confirming the importance of volcanic eruptions in illustrating the decadal-climate variability recorded in the paleoclimate proxy data for the past million years.

• 한국대기환경학회지
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• 제22권3호
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• pp.271-285
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• 2006

A two-dimensional photochemical transport model (2D PTM) is simulated to describe the transport and chemical reaction of ozone related to aerosols in the troposphere and stratosphere. The vertical profiles and total amounts of ozone, which are advected by both residual Eulerian circulation and the adiabatic circulation under certain circumstance, have been compared with the observation data such as ozonesondes, Brewer spectrometer, the Upper Atmosphere Research Satellite (UARS), and the Total Ozone Mapping Spectrophotometer (TOMS). As a result, we find that the observed distribution of ozone Is adequately reproduced in the model at middle and high latitude in the Northern Hemisphere as well as at Phang ($36^{\circ}\;02'N,\;129^{\circ}\;23'E$) in South Korea. In particular, the 2D PTM is well simulated in the ozone decrease due to the Pinatubo volcanic eruption in 1991. However, ozone mixing ratio are more underestimated than those of UARS and ozonesondes, because are very sensitive to the latitude of transport across the tropopause associated with both Rummukainen errors and off-line model. Relative mean bias errors and relative root mean square errors of ozone calculations using the 2D PTM are shown within${\pm}10%$, respectively.

• 한국지구과학회지
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• 제22권5호
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• pp.415-422
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• 2001

대류권과 성층권의 대기대순환에 관한 연구는 전지구 규모의 기후변동에 대한 인간활동의 영향을 이해하는 데에 있어서 매우 중요하다. 최근, 상부대류권과 성층권의 대기대순환에 있어서의 일년주기의 존재가 많은 연구에 의하여 보고되어졌다. 이 연구에서는 10년간(1985년 12월${\sim}$1995년 11월)의 자료에 대하여, 변형오일러평균방정식계의 운동방정식과 연속방정식을 이용하여 잔차평균자오면순환을 구하고, 그 순환과 100hPa면을 가로지르는 질량 플럭스들의 장기변동을 조사한다. 그 장기변동을 정량적으로 파악하기 위하여 중회귀통계모델을 사용한다. 특히, 이 연구에서는 이상기상과 전지구 규모의 기후변동의 원인으로서 알려진 엘니뇨현상과 관련한 대류권과 성층권의 평균자오면순환에 초점을 맞춘다. 연구의 결과는, 전지구 규모의 대류권-성층권 평균자오면순환은 엘니뇨현상과 준2년주기진동의 동풍 위상 동안에 강화되어지고, 라니냐현상과 준2년주기진동의 서풍 위상 동안에 약화되어진다는 사실을 보인다. 그리고, 1991년 6월에 있었던 피나투보 화산 폭발의 신호가 얻어진다. 그 화산 폭발 때문에 전지구 규모의 대류권-성층권 평균자오면순환은 급격히 강화되어진다.