Abstract：
Climate change has attracted significant attention due to its increasing impacts on various aspects of the world, and future climate projections are of vital importance for associated adaptation and mitigation, particularly at the regional scale. However, the skill level of the model projections over China in the past more than ten years remains unknown. In this study, we retrospectively investigate the skill of climate models within the Third (TAR), Fourth (AR4), and Fifth (AR5) Assessment Reports of the Intergovernmental Panel on Climate Change (IPCC) for the near-term projections of near-surface (2 m) air temperature changes in China. Those models are revealed to be skillful in projecting the subsequent climatology and trend of the temperature changes in China during 2002-2018 from several to ten years ahead, with higher scores for the climatology than for the trend. The model projections display cold biases against observations in most of China, while the nationally averaged trend is overestimated by TAR models during 2002-2018 but underestimated by AR4 models during 2008-2018. For all emission scenarios, there is no obvious difference between the equal- and unequal-weighted averages based on the arithmetic averaging and reliability ensemble averaging method respectively, however the uncertainty range of projection is narrowed after weighting. The near-term temperature projections differ slightly among various emission scenarios for the climatology but are largely different for the trend.
摘要：
由于气候变化对世界各个方面的影响越来越大，因此引起了人们的广泛关注。未来的气候预测对于相关的适应和缓解至关重要，特别是在区域范围内。然而,在过去的十多年中，模型预测中国的技能水平仍然未知。在这项研究中,我们回顾性调查了第三区域(TAR)内的气候模型技巧，第四（AR4），政府间气候变化专门委员会（IPCC）的第五次（AR5）评估报告，用于对中国近地表（2m）气温变化的近期预测。这些模型被证明可以巧妙地预测未来几年到十年2002-2018年中国随后的气候学和温度变化趋势，气候学得分高于趋势。模型预测显示，中国大部分地区的观测结果存在冷偏，虽然2002-2018年TAR模型高估了全国平均趋势，但2008-2018年AR4模型低估了全国平均趋势。对于所有发射场景，分别基于算术平均和可靠性集合平均法的等加权平均数和不等加权平均数之间没有明显差异，然而，加权后预测的不确定性范围缩小。近期温度预测在气候学的各种排放情景中略有不同，但在趋势上却大不相同。
