Review of the Research Progress in Global Warming Hiatus

From 1998 to 2012, the warming rate of global mean surface air temperature showed significantly slower than before, which is referred to as the global warming hiatus. The causes and underlying mechanisms of this phenomenon are currently a hot topic of climatic change research. The research significance of global warming hiatus was discussed and relevant research progress was reviewed from two perspectives of external forcings and internal variabilities. In term of external forcings, global warming hiatus is mainly affected by solar activities, volcanic eruptions, aerosols and stratospheric water vapor. With respect to internal variabilities, the warming rate of global mean surface air temperature slowdown is mainly related to the natural variabilities of the Pacific Ocean, the Atlantic Ocean, the Indian Ocean and the Southern Ocean and influenced by the related heat redistribution processes. During the global warming hiatus period, some energy is transferred and restored in the deep ocean so as to modulate the global warming rate, rather than there is a reduction of global total energy in the climate system. In addition, the partially coupled forcing pacemaker model experiment was also reviewed. The pacemaker experiment is a powerful tool for studying the characteristics, causes and underlying mechanisms of the global warming hiatus. Besides, some challenges resulted from the global warming hiatus, including the global energy imbalance, data, simulation and related policy-making were summarized, and future research directions were also discussed.     

全球变暖停滞的研究进展回顾

1998—2012年,全球平均地面增温速率较之前明显趋缓,出现全球变暖停滞现象,该现象的成因与机制是当前气候变化研究的一个热点领域。主要从外部强迫和内部变率2个角度回顾全球变暖停滞产生机制的研究进展。从气候系统外部强迫影响来说,全球变暖停滞主要受到太阳活动、火山爆发、气溶胶以及平流层水汽等的影响。从气候系统内部调控作用来看,全球增温速率减缓主要受到太平洋、大西洋、印度洋和南大洋自然变率以及相应的热量再分配过程的影响。全球变暖停滞期间气候系统内部能量并没有减少,其中一部分能量被转移并储存在了海洋中深层,从而对全球增温减缓产生影响。同时,重点回顾了针对部分耦合强迫作用的"起搏器"试验,该类试验是研究全球变暖停滞的特征、成因及机制的有力手段。此外,也总结了全球变暖停滞现象对气候系统能量收支平衡、资料、模拟以及相关政策制定等方面带来的挑战,展望了未来的研究重点。     

Assessment of the Decadal Prediction Skill on Global Land Summer Monsoon Precipitation in the Coupled Models of ENSEMBLES

Global monsoon precipitation plays a crucial role in the local social economy and global large-scale circulation and energy cycle. Using the decadal prediction output for 1960-2015 from ENSEMBLES Stream 2, the decadal hindcast skill of climate models on global land monsoon precipitation and the potential source of predictability were examined in this paper. It is found that the decadal variation of global and southern hemispheric land monsoon precipitation is not well hindcasted by ENSEMBLES. However, the Northern Hemispheric land Summer Monsoon (NHSM) precipitation in hindcast is well predicted, including the observed downward trend from 1960 to the late 1970s and upward trend since the 1990s. The main deficiency is that the minimum NHSM precipitation occured in mid-1970s, which is 10-year earlier than the observation, leading to poor prediction of NHSM precipitation from the mid-1980s to early 1990s. Mega-ENSO and Atlantic Multi-decadal Oscillation (AMO) are the two main factored that modulate the decadal variation of NHSM precipitation. The result shows that the relationships of NHSM precipitation with mega-ENSO and AMO in ENSENBLES are higher than the observation. The climate models well predicted the increase from 1960 to the late 1970s and decrease trend since the 1990s of mega-ENSO and AMO. It is the primary source of the prediction skill on NHSM changes during the two periods. Although AMO is well predicted by ENSEMBLES (highest correlation coefficient with observation is 0.85), the prediction skill of mega-ENSO is limited, leading to poor performance in predicting NHSM precipitation from the mid-1980s to early 1990s. Thus, improving the prediction of mega-ENSO can be seen as one important method of better decadal prediction of NHSM precipitation.     

全球气候变暖争议中的核心问题

综合分析了全球气候变暖争议中的3个核心问题:①全球变暖停滞了吗?回答是不一定。虽然根据HadCRUT3序列显示1999—2008年温度增量很小,但是这10年仍是过去30年中最暖的10年。而根据NASA GISS序列,则同期温度增量仍达到0.19℃/10a。目前全球地表气温在一个较暖平台上振荡,不能忽视自然气候变率。②气候变暖完全是由人类活动造成的吗?回答是否定的。虽然温室效应加剧可能是全球变暖的主要原因。但是,ENSO、太阳活动、火山活动、热盐环流等对全球变暖也有影响,在年代际及年际尺度上其影响甚至有时可能超过人类活动的作用。其中,太阳活动对气候变化的影响是需要重点考虑的因素。③气候变暖的影响有十分明显的迹象吗?回答是肯定的。近几年冰雪圈融化的速率及海平面上升的速率均超过了2007年IPCC第四次评估报告的估计,因此对未来SL上升的预估值也增加了。     

Advances and Challenges in the Study on the Tropical Rainfall Changes Under Global Warming*

Since tropical rainfall is important in the global energy and hydrologic cycle, the tropical rainfall changes under global warming have attracted extensive attention around the world in recent decades. The advances in the observational studies and model projection for the tropical rainfall changes under global warming were reviewed here. The frontiers in the mechanism of regional tropical rainfall changes and the approaches of rainfall change research are summarized. The large intermodel spread in the multi-model projections, the sources of uncertainty and the methods to reduce the uncertainty were also introduced. Finally, the challenges about the tropical rainfall changes were discussed.     

Rainfall Variability and Changes in Southern Africa during the 20th Century in the Global Warming Context

Rainfall variability and changes in Southern Africa over the 20th century areexamined and their potential links to the global warming discussed. After a shortreview of the main conclusions of various experiments with Global AtmosphericModels (GCM) forced by increased concentrations of greenhouse gases for SouthernAfrica, a study of various datasets documents the observed changes in rainfall featuresat both daily and seasonal time steps through the last century. Investigations of dailyrainfall parameters are so far limited to South Africa. They show that some regionshave experienced a shift toward more extreme rainfall events in recent decades.Investigations of cumulative rainfall anomalies over the summer season do notshow any trend to drier or moister conditions during the century. However, closeexamination reveals that rainfall variability in Southern Africa has experiencedsignificant modifications, especially in the recent decades. Interannual variabilityhas increased since the late 1960s. In particular, droughts became more intense andwidespread. More significantly, teleconnection patterns associated with SouthernAfrican rainfall variability changed from regional before the 70s to near global after,and an increased statistical association to the El Niño – Southern Oscillation (ENSO) phenomenon is observed. Numerical experiments with a French GCM indicate that these changes in teleconnections could be related to long-term variations in the Sea-Surface-Temperature background, which are part of the observed global warming signal.     

近20年气候变暖对北京时令旅游的影响--以北京市植物园桃花节为例

北京植物园桃花节是赏花专题时令旅游的典型代表,以近20年植物园桃花节的起讫时间、持续时间及相关气温、物候期等数据为依据,探讨了气候变暖对时令旅游的影响。结果表明：1994年前后桃花节开始日期存在着显著的均值差异,后一时段比前一时段约提前6天,植物园桃花节的开始日期在总体上响应了以山桃始花为代表的北京春季物候提前的变化趋势。同时,桃花节开始日期与上年山桃始花日期、上年年均温度存在显著相关性,反映人们对桃花节的决策是参照上一年的物候现象做出的,相对于气候年际波动存在1年的滞后。桃花节结束日期受人为因素影响较大,但总的来说气候变暖有利于桃花节持续日数的延长。此外,桃花节响应气候变化的滞后性,使得气候波动容易引起时令旅游产品的不稳定,不利于时令旅游的经济效益和社会效益。     

全球变暖对新疆水循环影响分析

随着全球气候变暖,新疆地区降水量、冰川数量、径流量、地下水位等自20世纪80年代中后期以来发生了很大的变化.通过对61个国家水文、气象站点20世纪50年代到2000年的降水量、气温、冰川、径流量、湖泊水量、地下水位的变化资料分析,探讨了新疆水循环的变化趋势和原因.结果表明:新疆地区降水量增加主要是由于全球水循环速度加快引起的.通过分析新疆高山冰川的变化,试图揭示全球气候持续变暖对新疆乃至整个西北地区水资源可能造成的巨大影响.     

Decadal Prediction Skill of the Global Sea Surface Temperature in the BCC_CSM1.1 Climate Model

This study assesses retrospective decadal prediction skill of Sea Surface Temperature (SST) variability in initialized climate prediction experiments (INT) with the Beijing Climate Center Climate System Model (BCC_CSM1.1). Ensemble forecasts were evaluated using observations, and compared to an ensemble of uninitialized simulations (NoINT). The results show as follows: ①The warming trend of global mean SST simulated by the INT runs is closer to the observation than that in the NoINT runs.②The INT runs show high SST prediction skills over broad regions of tropical Atlantic, western tropical Pacific and tropical Indian Oceans. ③ In the North Pacific and the east-central tropical Pacific Ocean, the prediction skills are very weak, and there are few improvements coming from the initialization in the INT runs. ④ In the southern Indian Ocean, the prediction skills of the INT runs are significantly larger than that of the NoINT runs, with the maximum skill at the 3~6 and 4~7 years lead time. The above-mentioned conclusions are similar to the results of other climate models. However, the prediction skill in the North Atlantic Ocean is much lower than that of other models, especially in the subpolar region. The low skills in the Atlantic Ocean may be attributed to the misrepresentation of the lead-lag relationship between the Atlantic meridional heat transport and the SST in the BCC_CSM1.1.     

全球气候变化的几个关键问题辨析

基于对全球气候变化事实与国家气候变化行动的分析,就当前全球气候变化科学认识和行动中的几个关键问题的不同观点与争论进行了辨析。指出：①应以比较确定的科学事实和“共同但有区别的责任”作为应对气候变化的出发点;②全球增温的幅度被高估了;③近百年全球变暖主要归因于人类活动的论断科学证据不足;④全球变暖的影响有利有弊,具体问题需具体分析;⑤气候预估不等于气候预测,气候预测尚待时日,气候预估的不确定性也非常大;⑥当前应对全球变暖的行动应采取“适应为主、减缓为辅”的战略。     

辽河盆地东部地区新老第三纪界面地层剥蚀量研究

辽河盆地新老第三纪地层间断面（N／E）形成于盆地由裂隐发育阶段向坳陷发育阶段转化的过渡时期，界面之下的裂隐沉积地层在早第三纪末期遭受了强烈剥蚀。在运用声波时差资料计算了近40口单井的地层剥蚀量的基础上，分析了地形对地层剥蚀的控制作用，恢复了辽河盆地东部凹陷北就地区N／E间断面地层剥蚀厚度等值线圈。结果显示该区域内N／E间断面地层剥蚀量的横向变化具有北部大、南部小、古河道两侧大、河道所在位置小的特点。     

Impacts of Initialization Schemes of Oceanic States on the Predictive Skills of the IAP Near-Term Climate Prediction System

Based on the near-term climate prediction system of the Institute of Atmospheric Physics (hereafter IAP-DecPreS), we developed two distinct initialization schemes for the Coupled Global Climate Models (CGCM), FGOALS-s2. The first scheme used the Incremental Analysis Update (IAU) to assimilate gridded oceanic temperature and salinity data derived from the EN3 dataset. The second scheme used the merge of the ensemble optimal interpolation (EnOI) and IAU scheme (hereafter EnOI-IAU) to assimilate raw observational oceanic temperature and salinity profiles. The predictive skills of the decadal prediction experiments based on the two schemes were compared. Several metrics including temporal correlation and root mean square skills score indicate that the experiment based on the EnOI-IAU shows significantly higher predictive skills in the Sea Surface Temperature (SST) anomalies in the North Pacific associated with the Pacific Decadal Oscillation (PDO), than the experiment based on the IAU. In contrast, for the Atlantic Multi-Decadal Oscillation (AMO), the predictive skills of the experiment based on the EnOI-IAU are lower than that based on the IAU. The AMO has two activity centers, located in the subpolar and tropical North Atlantic. The skills of the experiment based on the EnOI are close to that based on the IAU in the tropical North Atlantic, while much lower than the latter in the extratropical region due to a false simulation of the warming trend in the region.     

全球变暖情景下黑河山区水循环要素变化研究

利用有关水文气象台站的观测资料,对近50年来黑河上游山区流域降水、气温与径流深等水循环要素的变化进行了分析,结果表明：该区域的平均气温变化总体上呈上升的趋势,且其升温幅度高于全球过去50年的升温幅度;降水与径流的变化均呈增加的趋势,但增幅不是十分显著,且径流增长的增幅要大于降水量,这意味着径流的增长并不完全依赖降水的增加,气温上升导致的冰川和高山积雪及地下冻土层融水增加也是影响黑河上游山区流域径流变化的重要原因。根据降水和气温未来的变化趋势,预计在未来50年中, 除非遭遇到特别极端的气候组合,黑河山区径流仍将维持过去50年来缓慢增加的趋势,但增幅非常有限,最大变幅基本在目前多年均值的±5%左右。     

A Comparative Research on Climatic Characteristics of Jianghuai Cyclones in Rainfall Season between Warming and Cooling Stages

By EOF, Power spectrum and nonlinear mapping methods, the temperature time series of May to July in Jianghuai river basins from 1948-2014 (67 years) were objectively divided into several climate stages. The time series were divided into three climate stages with similar lengths: the stage with its air temperature trend going downwards stage (1948-1970); the stage with its air temperature trend going upwards (1971-1994) and the stage with its air temperature trend going gentle upwards (1995-2014). Their climate characteristics can be quantified by a special climate index. Then, the statistic characteristics of Jianghuai cyclones in the three climate stages were compared with the cooling or warming trends. The results showed that characteristic evolutions of the frequency of yearly average of Jianhuai cyclones, the cyclones with their life cycles in the area longer than 48h, the cyclones with three types of thickness, shallow and bottom shapes classified according to the cyclone height, the cyclones with three kinds of zonal, meridional, and circular trajectory, responded to the temperature changing trends in the three climate stages. The cooling trends of the stage temperature restrained the activity of Jianghuai cyclones, and the warming trends of the stage temperature promoted the cyclone’s development, maintaining, activity, and also led cyclone moving towards to north further. The composite analysis of cyclone structures showed that the evolution characteristics in the center intensity, temperature grads, the maxima velocity of jet of the cyclones, and the intensity, length and position of the vapor flux passage of the Jianghuai cyclones, also the intensity, thickness, the positions of the warm and cold air masses within the cyclones, all responded to the trend change of stage temperature including cooling, warming and gentle warming. The results show clearly that temperature cooling reduces the intensity of cyclone structures and restrains the activity of cyclones in the temperatures trend down stage. The temperature warming enhances the stable development and strengthening of cyclone structure,and maintains the activity of cyclones in the temperature warming stages.     

全球变化背景下的敏感性研究综述

敏感性研究是全球变化科学研究的重点领域,通过认识全球变化和生态安全之间的相互关系,为人类适应全球变化提供科学依据。基于对敏感性概念的辨析,探讨了全球变化背景下敏感性的科学内涵,提出了敏感性研究的框架,列举了敏感性分析与评价各自的研究方法、对象和目标,从生物学实验、实地观测、计算机模型以及统计分析4个方面系统总结了敏感性分析的方法与实践,概述了非脆弱性和脆弱性框架下的敏感性评价方法与实践。发现在很多研究中敏感性评价是脆弱性框架中的重要一部分,但是评价自然生态系统对环境变化的敏感性则往往不依赖于脆弱性框架,是独立完整的研究。最后总结了敏感性研究的阶段性特征,指出了未来的研究重点和发展方向。     

Studies on the Coral Reefs of the South China Sea: From Global Change to Oil-Gas Exploration

Studies on the coral reefs of the South China Sea (SCS) was the theme of the 6th Session of the 3rd Conference on Earth System Science (CESS) in Shanghai, 2014. This session discussed the most recent study developments on the SCS coral reefs, including coral reefs’ responses to global changes, coral reefs’ records on past climatic variations, and the activities about constructions and oil gas explorations in the coral reefs areas of the SCS. Disturbed by intensive anthropogenic activities and global climate warming, coral reefs in the SCS have declined dramatically, reflecting the up to 80% decrease of living coral cover and many areas having less than 20% of living coral cover. Geochemical data of SCS coral skeletons clearly show that since the Industry Revolution, the pollution situation of the SCS have dramatically increased and the seawater pH values have been continuously lowering, i.e. oceanic acidification. All these environmental phenomenon are further stressing the healthy development of the coral reef ecosystem in the SCS. Meanwhile, the poor coral reef ecosystems in the SCS are facing more anthropogenic disturbances such as coastal developments and engineering constructions. Obviously, the SCS coral reefs will be faced with more environmental challenges in the coming future. We therefore suggest that the policy makers should realize the extreme importance and the fragile of the coral reef ecosystems, and scientifically and with great cautions design construction project when in coral reef areas. We initiated the concept of “green engineering” for future developments in coral reef areas. Coral reefs are widely spreading in the whole SCS, and most of them developed since Miocene. Variations in coral reef structures provide good future oil-gas exploration. Because the SCS coral reefs have a long-developing history and a wide spatial distribution, they provide great potential in recording past environmental changes.     

全球变化下地表反照率研究进展

地表反照率表征地球表面对太阳辐射的反射能力,决定着地表与大气之间辐射能量的分配过程,是影响地球气候系统的关键变量。在全球变化日益突出的今天,地表反照率与全球变化的相互影响机制已经成为地球科学研究领域的热点问题之一。地表反照率的细微变化,会影响到地气系统的能量收支平衡,进而引起区域以至全球气候变化。详细介绍地表反照率影响...     

全球变化研究进展和趋势

-概述了国际全球变化研究计划（ESSP、IGBP、WCRP、IHDP、DIVERSITAS）新近的研究战略调整和研究重点,在对国际全球变化研究成果综合分析的基础上,总结了全球变化研究的阶段性理论进展,归纳了全球变化研究的特点和趋势。     

吉林中部平原区浅层地下水温度对全球气候变暖的响应

水温变化除引起水的多种物理性质的变化外, 还会引起水化学反应速度等方面的变化. 以吉林中部平原地区为例, 对影响浅层地下水温因素的分析发现, 研究区浅层地下水温变化的本质原因是受全球气候变化的影响, 降水量的减少以及地下水位的下降对浅层地下水温受气候变化的影响起到削减作用. 通过对全区近200眼地下浅层观测井水温的多年变化分析, 发现在研究区气温近20 a来升高(约1.5 ℃)的影响下, 浅层地下水温从1978年的7 ℃左右上升到2001年的8.3 ℃, 在20余年间水温升高约1.3 ℃     

Trend of Salt Lake Changes in the Background of Global Warming and Tactics for Adaptation to the Changes

Salt lakes are a mirror of climatic changes and provide holographic records of environmental changes of lakes. According to a study of geological hazards in typical salt lake areas in China and other regions, the authors explain how geological hazards in salt lake areas are caused by natural agents and how humans can seek benefits, avoid hazards and reduce losses on the premise that they have monitored and mastered the trend of salt lake changes in advance and even can store flood and recharge water in lakes and extract saline resources. The climate