利用CMIP6模式模拟的多层土壤温度资料，结合鄂陵湖草地站土壤观测资料和欧洲中心ERA5再分析资料，评估了BCC陆面过程模式对青藏高原土壤冻融过程的模拟能力。结果表明：BCC-CSM2-MR对青藏高原冻融总天数，特别是对于消融过程阶段的模拟接近观测值，但其完全冻结阶段和消融过程阶段的日期都有所推迟，可能与陆面模式物理参数化过程不完善导致土壤温度下降更慢有关。BCC-CSM2-MR对青藏高原土壤冻结时段前期的冻土深度变化曲线模拟效果最佳，但由于网格分辨率低且对地形刻画不准确，BCC-CSM2-MR不能模拟出青藏高原西南部相间分布的冻土深度特征。BCCCSM2-MR可以模拟青藏高原土壤温度在1985～2014年的升高趋势。对于气候倾向率空间分布，BCC-CSM2-MR模拟结果相较于集合平均，在青藏高原东北部偏低而西部偏高，且不能模拟出北部存在的少量相对低值区域。

利用基于BCC-CSM1.1m模式建立的第2代季节预测模式系统1984—2019年历史回算数据,客观评估该模式对1月和4月欧亚积雪覆盖率(snow cover fraction,SCF)气候态和年际变化的预测技巧,分析模式预测偏差产生的可能原因。结果表明:BCC-CSM1.1m模式在超前0～2个月对欧亚大陆SCF具有一定预测技巧,对4月SCF的预测能力明显高于1月,1月预测技巧在欧洲西部地区最高,4月在西西伯利亚地区最高。SCF的预测结果在除青藏高原外的大范围地区表现为系统性偏低,预测偏差在1月随着起报时间的增长没有明显变化,而在4月随着起报时间的增长,关键区偏差由负转正并逐渐增大。分析表明,SCF预测偏差与模式中近地面气温的预测偏差有直接关系。除此之外,SCF的预测偏差部分源于模式本身的系统性偏差,模式分辨率以及参数化方案可能是预测结果在积雪覆盖率接近100%的高纬度地区明显偏低的原因。

We used an online aerosol-climate model (BCC_AGCM2.0_CUACE/Aero) to simulate effective radiative forcing and climate response to changes in the concentrations of short-lived climatic pollutants (SLCPs), including methane, tropospheric ozone, and black carbon, for the period 2010-2050 under Representative Concentration Pathway scenarios (RCPs) 8.5, 4.5, and 2.6. Under these three scenarios, the global annual mean effective radiative forcing were 0.1, -0.3, and -0.5Wm(-2), respectively. Under RCP 8.5, the change in SLCPs caused significant increases in surface air temperature (SAT) in middle and high latitudes of the Northern Hemisphere and significant decreases in precipitation in the Indian Peninsula and equatorial Pacific. Global mean SAT and precipitation increased by 0.13K and 0.02 mmd(-1), respectively. The reduction in SLCPs from 2010 to 2050 under RCPs 4.5 and 2.6 led to significant decreases in SAT at high latitudes in the Northern Hemisphere. Precipitation increased slightly in most continental regions, and the Intertropical Convergence Zone moved southward under both of these mitigation scenarios. Global mean SAT decreased by 0.20 and 0.44K, and global averaged precipitation decreased by 0.02 and 0.03 mmd(-1) under RCPs 4.5 and 2.6, respectively.

This study simulates the effective radiative forcing (ERF) of tropospheric ozone from 1850 to 2013 and its effects on global climate using an aerosol-climate coupled model, BCC AGCM2.0.1 CUACE/Aero, in combination with OMI (Ozone Monitoring Instrument) satellite ozone data. According to the OMI observations, the global annual mean tropospheric column ozone (TCO) was 33.9 DU in 2013, and the largest TCO was distributed in the belts between 30A degrees N and 45A degrees N and at approximately 30A degrees S; the annual mean TCO was higher in the Northern Hemisphere than that in the Southern Hemisphere; and in boreal summer and autumn, the global mean TCO was higher than in winter and spring. The simulated ERF due to the change in tropospheric ozone concentration from 1850 to 2013 was 0.46 W m(-2), thereby causing an increase in the global annual mean surface temperature by 0.36A degrees C, and precipitation by 0.02 mm d(-1) (the increase of surface temperature had a significance level above 95%). The surface temperature was increased more obviously over the high latitudes in both hemispheres, with the maximum exceeding 1.4A degrees C in Siberia. There were opposite changes in precipitation near the equator, with an increase of 0.5 mm d(-1) near the Hawaiian Islands and a decrease of about -0.6 mm d(-1) near the middle of the Indian Ocean.