By Glenn Richardson,2014-10-02 17:07
15 views 0

East Asian weather and climate Project: Stratospheric processes and their roles in

    Principle Investigator: LÜ Daren

    Supported by: National Basic Research Program

    Contact Info

    Dr. BIAN Jianchun

    Institute of Atmospheric Physics, Chinese Academy

    of Sciences Scientific significance Stratosphere, the second major layer of Earth's

    Tel: +86-10-82995078 atmosphere, just above the troposphere, is situated

    Fax: +86-10-82995073 between about 10 km and 50 km altitude above the see

    level. Although the stratosphere occupies only 15% of

    the whole global airmass, the atmospheric processes in

    the ozone depletion was caused by the CFCs which were this layer have significant impacts on the Earth climate.

    made and released by human beings. Under the appeal The stratosphere embraces 90% of the total ozone, which

    of the international scientific community, from 1987 serves as an umbrella to shield the whole biosphere living

    onwards, national governments joined the Montreal and evolving in the Earth from ultra-violet radiation.

    Convention and other conventions on the protection Stratospheric compositions, such as ozone, water vapor

    of the ozone layer in efforts to reduce and cease the and volcanic aerosol, make great effect, by absorbing and

    production and use of CFCs and other ozone-depleting scattering solar short-wave radiation, on the atmospheric

    substances (ODS). As a result of over two decades’ radiation balance in the surface and troposphere; the

    efforts, the ozone depletion has shown recovery signs infrared radiation caused by the greenhouse gases in the

    since the end of 1990s. The last scientific assessment stratosphere is an important component in the radiation

    report on the change of ozone layer organized by WMO budget of the climate system. Studies in recent decades

    and UN Environment Program in 2006 made a prediction show that the stratospheric processes, whether intra-

    that the stratospheric ozone had a possibility to recover seasonal anomaly or decadal variability, play an important

    to the level before 1980s in 2050 due to the combination role in the extreme weather event or climate variation in

    effect of the continuous decrease of ODS and the the troposphere, respectively.

    Long-term trend of the ozone layer in the background of climate warming is a hot topic in the

     research area of global change. During the 1980s and 1990s, ozone was depleted continuously in the

     stratosphere, and particularly extreme ozone depletion was observed in the Antarctic spring every year, known

     as Antarctic ozone hole. Its area kept growing, and 2 reached nearly 30,000,000 kmin September 2000. The

     severely influence of the atmospheric ozone depletion

     on the biosphere security and human health has Schematic figure of the received close attention from the international scientific atmospheric vertical structures. community. Intensified scientific research shows that

    Projects Underway Vol.23 No.4 2009

     To project the climate change trends in the stratosphere in the context of stratospheric ozone recovery and increase in global greenhouse gases; and, To reveal the mechanisms by which the stratospheric processes can impact the weather and climate in East Asia.

     Scientific issues How are the dynamical, chemical, and microphysical

     processes coupled in the UTLS region, and particularly over East Asia? What are the multiple scale processes in the Schematic interactions among dynamical, radiative, chemical, stratosphere- troposphere coupling and their coupled and microphysical processes in the stratosphere and mechanisms, and in particular how the weather and climate troposphere. in East Asia are affected by stratospheric processes? enhancement of the radiative cooling effect caused by How will chemistry and climate interact under the the increase of greenhouse gases in the stratosphere. external forcing, such as the change caused by human However, these are only preliminary results, and there activity and solar radiation?

    is great uncertainty in predicting the long-term trends How will the stratosphere evolve in the following in the ozone layer. What must be emphasized is that decades under the joint action of two major trends: the the climate of the 21st century to restore the ozone ozone layer recovery and the continuous increase of layer will be completely different from the background greenhouse gas emissions? climate prior to 1980. In such a state of global climate

    change, the ozone layer recovery, not only is impacted Research strategies

    by the climate change, but also acts as a major driving Experiment campaign will be conducted to observe forcing because of ozones absorption of short-wave the stratosphere-troposphere exchange processes in East radiation and emission of long-wave radiation. Asia, by synthesizing and integrating a variety of data,

    Stratospheric process and its role in climate is a focus so as to analyze the atmospheric processes and structures in the research of the global climate system. The research in the UTLS region. Numerical simulation and physical with regard to the role of stratospheric processes in climate diagnosis will be conducted to reveal the stratosphere- change and climate variability has been carried out over troposphere airmass and minor gases exchange 20 years. Since the East Asia has a very important role and characteristics and mechanisms in the East Asian region, a significant regional feature in the global stratosphere- and their roles in the global balance of the atmospheric troposphere coupling, thus to enhance the research and compositions. Descriptions of stratosphere-troposphere understanding of the regional characteristics in East Asia is exchange process in the chemistry-climate coupled model an important and key aspect. will be improved to reveal the impact of the atmospheric

    composition changes on the stratospheric ozone layer Scientific goals and global climate. A variety of data and numerical

    simulations will be analyzed to quantify the role of To reveal the structures of the stratosphere over

    upward propagating atmospheric waves originated in the East Asia, and particularly finer structures in the upper

    troposphere and lower stratosphere (UTLS); troposphere in East Asia on the stratospheric circulation.

    Linkage between stratospheric circulation anomalies and To understand the stratosphere-troposphere

    interaction in more details and its mechanism; the weather and climate in East Asia will be analyzed, so

    as to reveal the potential stratospheric harbingers in the To understand the mechanisms in the chemistry-

    weather and climate forecasting in the East Asia. climate interaction;

Project: Variability of the water and energy cycles and their impact on the

    extreme climate over China under the global warming background

    Principle Investigator: WANG Huijun

    Supported by: National Basic Research Program

    Contact Info

    Prof. Wang Huijun

    Institute of Atmospheric Physics, Chinese Academy

    of Sciences Background Tel: 86-10-62041081

    China is a country with high climatic sensitivity. Every Email: year, it is hit by various extreme climate events, which

    cause heavy casualties and enormous economic losses. Especially since the middle 1970s, extreme events, such as droughts/floods, heat waves, intense snowfall and frost, have been more frequent and intense in China, exerting much stronger impact on society, industrial and economic systems, and natural and managed ecosystems. Thus, to reduce the extreme impact have become an urgency of the national development and a key issue in the climate Prof. W ang Huijun, change studies, receiving increasing attention from both the Principle Investigator of governments at all levels and scientists. the project. Following the national demand, this project, as a part of the National Basic Research Program (also called 973 eastern monsoon regions, northwestern arid and semiarid Program), entitled “variability of the water and energy regions, and the Tibetan Plateau. These field experiments cycles and their impact on the extreme climate over China are designed to reveal the variation features of the energy under the global warming background” was launched with and water cycles under three kinds of typically underlying the aim to improve the understanding of the spatial and surface in China.

    temporal change features of the extreme climate events in Via studies on the relationship between the

    China, further explore their variability mechanisms in the variability of the extreme climate events and the energy and context of water and energy cycles, and then advance the water cycles over the three regions mentioned, module five prediction ability of such events. is to explore the possible impact of the different features of

    The project is divided into seven modules. energy and water cycles on the occurrence of the extreme

    Module one is to investigate the special and climates over China.

    temporal changes and trends of these climate extremes, and Combining the observations from the field

    their relationship with global warming and the East Asian experiment in this project, the remote sensing data from monsoon circulations, via the observational daily data of satellite on the land surface processes, and corresponding the 20th century. observational data derived from the previous projects,

    Considering the crucial role of the water and module six is to optimize the description of land surface energy cycles in the climate variability, in module two- processes as well as water and energy cycles in numerical four, the field observational experiments are set up in climate model, develop a high resolution nested regional

    Projects Underway Vol.23 No.4 2009

     of Chinas ability in simulation and prediction of extreme climate events.

     Using the model simulations of this project, module seven presents the possible variability of the extreme climate events of China in the future 10-20 years with respect to the global warming. The execution of this project will not only fulfill a scientific theoretical foundation for research on the hydro- energy-climate interaction in the climate system, but also improve the prediction capability of extreme climate events in China, expediting the transfer of scientific results to operational applications. The prediction systems which Participants of the launching ceremony of this project.

     will be set up by this project can finally provide with useful information for the decision-making and investing climate model, and also study the statistical predict method.

    of policymakers, managers, and individuals so as to make The improvements to the land surface and hydrological

    models and statistic prediction method made by the contribution to the disaster prevention and mitigation, research team are expected to lead to great enhancement economic and social sustainable development of China. Project: Equilibration relation of terrestrial carbon, nitrogen and water fluxes

    and its response mechanisms to the environment in China

    Principle Investigator: YU Guirui

    Supported by: National Basic Research Program

    Contact Info

    Prof. Yu Guirui

    Institute of Geographic Sciences and Natural Background and significance Resources Research, Chinese Academy of Sciences Negotiations for reducing the emissions of greenhouse gases have become one of the topics of international Tel: +86-10-6488-9432 diplomacy since the Kyoto Protocol was adopted in 1997 Fax: +86-10-6488-9432 and the Bali Roadmap was proposed in 2007. Now China

    faces much pressure in dealing with this problem as well as

    great challenges in balancing social-economic development that drive ecosystem changes. Meanwhile, variations in with resource conservation and environmental protection. these cycles will send feedbacks to global change. How the Hence, it is a necessary strategic choice for China to rise in temperatures and COconcentrations, as well as the 2

    enhance the terrestrial carbon sinks and reduce terrestrial changes in precipitation pattern and nitrogen deposition carbon emissions by controlling industrial emissions. influence the terrestrial carbon sequestration and its spatio-

    Terrestrial carbon, nitrogen, and water cycles, which temporal pattern? It remains one of the most important are strongly influenced by global change, are key processes scientific questions in recent years. The cycles and their

To quantify the ecological stoichiometry characteristics of carbon, nitrogen, and water fluxes and

their responses to climate change, based on previous studies by the North-South Transect of Eastern China

(NSTEC), China Grassland Transect (CGT), Chinese National Ecosystem Observation and Research Network

(CNERN), and ChinaFLUX-CN.

Key scientific and technologicalquestions

The coupled action among carbon (CO, CH), nitrogen 24 Contents and techniques for integrated carbon, nitrogen, and (NO, NO, NH) and water (HO) between ecosystems 232water fluxes observation in terrestrial ecosystem.

and the atmosphere behaves an ecological stoichiometric equilibrium. In the natural condition, the property relation of carbon, nitrogen, and water fluxes keeps relative stable

(coupling relation). But if the environmental condition changes, the equilibrium may be broken (decoupling

phenomenon). To assess the terrestrial ecosystem carbon sinks and find out the spatial pattern and trend in China under the global change, two scientific questions should be dealt with: What kind of equilibrium relation and spatio- temporal variations exist between the carbon, nitrogen and water fluxes of the terrestrial ecosystems? How Multiple factor experiments for carbon, nitrogen, and water cycles processes research. environmental factors drive the equilibrium relation?

How the carbon, nitrogen, and water fluxes responses to climate change have not been well understood of the terrestrial ecosystems and their equilibrium due to the limitation in understanding the double driving relation response to the global change (such as the rise mechanisms of climate change and human activities’ in temperature, changes in precipitation patterns) and influence and the complexity of coupling the cycles. different disturbances (such as the increase in nitrogen Primary knowledge and prediction are still uncertain. deposition, overgrazing)? Therefore, the project is essential for fighting against global

change, improving ecosystem management, ensuring ecosystem safety, and promoting the scientific innovation in the earth system science and the global change science.


To establish a scientific research platform for studying carbon, nitrogen, and water cycles of terrestrial ecosystems in China, which is dubbed as ChinaFLUX-CN; To conduct a long-term observation network and a multiple factor experiment network; To develop a new process-based model coupled with remote sensing for carbon-nitrogen-water cycles modeling; and, A schematic diagram of this research project.

    Projects Underway Vol.23 No.4 2009

    In addition, a methodology of ecosystem process-based Methods

    model data fusion system will be established, including By collecting all kinds of observation and experimental

    an inversion method for the new remote sensing data, the data along NSTEC and CGT, the scientists mainly use

    multiple data assimilation methods, and the model data observation network, manipulative experiment, model fusion methods. development and synthetic analysis methods.

    Project: Ocean circulation in the western tropical Pacific and low frequency

    variability of warm pool

    Principle Investigator: HU Dunxin

    Supported by: Major Program of the National Natural Science Foundation of China

    Contact Info

    Prof. Hu Dunxin

    Institute of Oceanology, ChineseAcadem y of Sciences Background Email: The Tropical North Pacific (TNP) features a Tel: 86-532-82898678 complicated ocean circulation system and is termed as a Fax: 86-532-82898677 crossroad and a major pathway for different waters from

    ambient regions to enter the equatorial thermocline. The

    North Equatorial Current (NEC) and the South Equatorial

    However, our understanding of the mean circulations Current (SEC) flow and converge in the western TNP,

    in the TNP remains incomplete. For instance, the origins while the Kuroshio, the North Equatorial Countercurrent

    and fates of the undercurrents, such as the Mindanao (NECC) and the Indonesian Throughflow (ITF) originate

    Undercurrent, Luzon Undercurrent, North Equatorial and flow out from there. The changes in the TNP water

    Undercurrent discovered in the last two decades, and properties and ocean circulation can influence the heat

    the water exchanges between the TNP and its adjacent and freshwater budget of the warm pool and hence the

    regions are still poorly understood owing to scarce and atmospheric deep convection, modulate the ENSO cycle,

    inadequate observations and little long-term, moored, and impact the East Asian monsoon (EAM) variability, as

    direct measurements of currents. This severely hinders the well as development and evolution of the tropical cyclones

    understanding of the maintenance mechanism and low- (Fig.1).

    frequency variability of the warm pool.


     This project is designed to observe, simulate, understand the structure and dynamics of the western TNP ocean circulation and its role in low-frequency modulation of both regional and global climate, including the warm

     pool, ENSO, EAM, and the tropical cyclones so as to Fig.1 A scheme shows the role of the tropical northwestern finally help improve the prediction of those oceanic and Pacific (warm pool) in climate.

atmospheric phenomena. Specific goals include: Key scientific questions

    To reveal the 3-D structure, variability and its The 3-D structure of the LLWBC system, its

    mechanism of the LLWBC (low latitude western boundary variability mechanism, and interactions with other currents; current) system in the north Pacific; The role of nonlinearity in the variability of 3-D

    To establish a dynamical framework of 3-D LLWBC system; and,

    circulation theory, which can well describe the LLWBC The controlling mechanism of heat and mass

    system; and, transport by the LLWBC system in recharging and

    To understand the role and mechanism of the LLWBC discharging processes of the warm pool. system in low frequency variability of the warm pool.

    Implementation of the project Research tasks Since the LLWBCs in the northern Pacific are in a 3-D structure of the LLWBC system in the north complex, nonlinear, and dynamical system, the goals of this Pacific and its variability mechanism: NEC bifurcation project will be reached through ocean-, atmosphere- and into the Kuroshio and MC; NEC-MC and SEC-NGCC mathematics-interdisciplinary study, integrating observation, confluence; subsurface currents, such as MUC, NGCUC, numerical modeling, and theoretic analysis as a whole. The EUC, LUC, NEUC and their relationship. study domain and observation design are showed in Fig.2. Non-linear dynamics of the LLWBC system:

     Interaction between the upper and subsurface circulations and relevant processes; non-linear behavior of NEC

     bifurcation and MC/NGCC confluence; role of mixing in upper-subsurface circulation interaction. Role of the LLWBC system in low frequency variability of the warm pool: Temporal and spatial characteristics and variability of heat transport in the LLWBC system; heat budget in the warm pool on seasonal to interannual time scales; relative importance of the roles of heat transport by LLWBCs from both hemispheres in variability of the warm pool. Fig.2 Study region of this project and its observation design.

Project: The potential of soil carbon sequestration and greenhouse gas

    emission reduction in croplands of China

    Principle Investigators: SHI Xuezheng, CAI Zucong & YU Dongsheng

    Supported by: Major Research Cluster Program of Chinese Academy of Sciences

    Contact Info Background Prof. Shi Xuezheng

    The Kyoto Protocol, which has already come into force Institute of Soil Science, Chinese Academy of Sciences officially, makes it clear that developing countries assume no E-mail:

     emission reduction obligations during the first commitment

    Projects Underway Vol.23 No.4 2009

     period before 2012. This, however, does not mean that China

     will still assume no such obligations after 2012. With the rapid economic development and the sustained population

     growth, Chinas energy consumption and greenhouse gas emissions will increase continuously. China is likely to

     overtake the US to become the worlds No.1 COemitter in 2 around 2025. Since China will face an enormous pressure of

     emission reduction in the near future, we have to make full preparations in advance to maintain our national interests

     and to provide theoretical basis and data support for the responsibility sharing negotiations ahead. Article 3.4 of the Kyoto Protocol proposes that carbon emissions originated from economic development can be set of f by increasing carbon pools in the -1ecosystem. Therefore, how to recollect and sequester the A dynamic change of soil organic matters (g kg) in Taihu Lake region from 1980 to 2000. COemitted from energy consumption and reduce the 2 emissions of CH/NO from agricultural development has 42Main research contents now become a hot topic for research around the world. It The characteristics of carbon pools and greenhouse

    is of great theoretical and practical significances to study gas emissions (and its driving factors) in Chinas croplands,

    the potential of carbon sequestration and greenhouse gas especially the evolution of organic carbon storage in the

    reduction in croplands of China. soil, the regional differentiation of CH/NO emission, and 42

    the major driving factors; Key scientific issues Agriculture-based technical measures and approaches

    Chinas potential to increase carbon pools to enhance carbon sequestration and CH/NO emission 42and reduce CH/NO emission in croplands, and the reduction in croplands, which focuses on the techniques that 42

    can be easily popularized and carried out, as well as their corresponding technical measures and approaches to

    mechanisms and implementation methods; and, bring this potential into full play while maintaining soil

    productivity and grain yield; The potential of carbon sequestration and emission

    The working mechanism of various technicalreduction in these croplands, by developing a scientific

    estimation model to reveal the spatial distribution pattern measures and their combination; etc.