Several scenario experiments of the IPCC 4th Assessment Report(AR4)are performed by version g1.0 of a Flexible coupled Ocean-Atmosphere-Land System Model(FGOALS)developed at the Institute of Atmospheric Physics,Chinese Academy of Sciences(IAP/CAS),including the"Climate of the 20th century experiment","CO2 1%increase per year to doubling experiment"and two separate IPCC greenhouse gases emission scenarios A1B and B1 experiments.To distinguish between the different impacts of natural variations and human activities on the climate change,three-member ensemble runs are performed for each scenario experiment.The coupled model simulations show:(1)from 1900 to 2000,the global mean temperature increases about 0.5°C and the major increase occurs during the later half of the 20th century,which is in consistent with the observations that highlights the coupled model’s ability to reproduce the climate changes since the industrial revolution;(2)the global mean surface air temperature increases about 1.6°C in the CO2 doubling experiment and 1.5 ° C and 2.4°C in the A1B and B1 scenarios,respectively.The global warming is indicated by not only the changes of the surface temperature and precipitation but also the temperature increase in the deep ocean.The thermal expansion of the sea water would induce the rise of the global mean sea level.Both the control run and the 20th century climate change run are carried out again with version g1.1 of FGOALS,in which the cold biases in the high latitudes were removed.They are then compared with those from version g1.0 of FGOALS in order to distinguish the effect of the model biases on the simulation of global warming.
利用AOML(Atlantic Oceanographical and Meteorological Laboratory)SVP漂流浮标的海表面温度数据,针对30°S以南的南大洋海域,对目前主要使用的微波遥感产品(AMSR-E,Ad-vanced Microwave Scanning Radiometer for the Earth Observing System)反演的SST进行了较为系统的评估。结果表明,AMSR-E SST比浮标数据偏冷,偏差为-0.01℃,标准差为0.70℃。夏季的偏差为0.004℃,标准差为0.64℃;冬季的偏差为-0.06℃,标准差为0.75℃,冬季的偏差和标准差较大。温差ΔT受流速影响,随着流速的增大而减小,且这种趋势在夏季更为显著。具备托伞结构的浮标与总体情况基本一致,而无托伞结构的浮标受流速的影响要大一些。同时,温差ΔT受水汽的影响,随着水汽的增加而减小,且这种影响在冬季更大一些。进一步对4个穿极和绕极浮标的追踪分析表明,温差ΔT受大洋海流系统的影响显著。在海流大的大西洋边界流和南极绕极流中,温差ΔT的不确定性要明显大于总体情况。
