Spring Land Surface and Subsurface Temperature Anomalies and Subsequent Downstream Late Spring-Summer Droughts/Floods in North America and East Asia

北美和东亚春季陆地表面和地下温度异常以及随后的下游春夏末干旱/洪水

• 批准号: 1849654
• 负责人: Yongkang Xue
• 金额: $ 68.82万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-06-15 至 2024-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1849654&HistoricalAwards=false
• 关键词: Spring; Land; Surface; Subsurface; Temperature

Episodes of extreme events, such as droughts and floods, can have serious societal, agricultural, economic, and ecological impacts. Basin-wide tropical sea surface temperature anomalies are known to play a major role in causing these extreme events. The linkage of these extreme hydrological events to tropical sea surface temperature anomalies allows us to predict them with useful skill at a long lead time in advance ranging from few months to few years. This project aims to explore the idea for the first time to utilize the information of spring land surface temperature/subsurface temperature anomalies over the western high elevation areas in North America and East Asia for the prediction of late spring/summer droughts or floods over the eastern part of the continents. The results from this research would be useful for the sub-seasonal to seasonal prediction community. This project is a direct response to the new initiative "Impact of initialized land temperature and snowpack on sub-seasonal to seasonal prediction" recently developed by the Global Energy and Water Exchanges (GEWEX) Program, which involves more than 30 institutions worldwide. Findings of this NSF project should provide valuable information to the GEWEX community. Knowledge gained in this research will be disseminated through classroom teaching, short course training classes as well as the GEWEX initiative. Unlike predictions using sea surface temperature, which uses sea surface temperature as a lower boundary condition for atmospheric models, the PI will use the information of spring land surface temperature (LST) and subsurface temperature (SUBT) anomalies as initial conditions in the land component of coupled climate models. The main hypothesis is that LST and SUBT anomalies in early Spring hold the information about the abundance of water locked in frozen ground (i.e., the amount of snow/ice on the ground and in the frozen surface layer below) to be melted in later Spring and early Summer. The more snow/ice on the ground and in the frozen surface layer below is, the longer the seasonal transition from Spring to Summer is. The timing of such seasonal transition over high elevation areas in the west plays an important role in setting up the circulation pattern downstream over the low elevation areas in the east. The strength as well as length of its interactions with the circulation pattern over the low elevation areas controlled by land-ocean temperature contrast would affect the occurrence of droughts or floods in late spring/summer over the eastern part of the continents. The research will run various numerical simulations using global and regional models under different climate and weather conditions (i) to understand the mechanisms for the downstream influences of LST/SUBT anomalies, (ii) to compare their effects with SST anomalies, (iii) to identify and distinguish roles of snow and soil moisture in contributing to soil memory and preserving the LST/SUBT anomalies, and (iv) to explore characteristics of soil layer memory and LST/SUBT anomalies and the causes of the spring LST/SUBT anomalies. The project will also develop a new SUBT initialization methodology for operational models to better utilize SUBT information for sub-seasonal/seasonal forecasts in spring/summer seasons.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

干旱和洪水等极端事件的发作会对社会、农业、经济和生态产生严重影响。已知整个盆地的热带海表温度异常在造成这些极端事件中起主要作用。这些极端水文事件与热带海洋表面温度异常之间的联系，使我们能够在几个月到几年的较长时间内用有用的技巧预测它们。本项目旨在首次探索利用北美和东亚西部高海拔地区春季地表温度/地下温度异常信息预测大陆东部春末/夏末旱涝的思路。研究结果对分季节到季节预报具有一定的参考价值。该项目是对全球能源和水交换计划（GEWEX）最近提出的“初始化土地温度和积雪对分季节到季节预测的影响”新倡议的直接回应，该计划涉及全球30多个机构。这个NSF项目的发现应该为GEWEX社区提供有价值的信息。在这项研究中获得的知识将通过课堂教学、短期培训班和GEWEX倡议传播。与使用海表温度作为大气模式下边界条件的预测不同，PI将使用春季陆地表面温度（LST）和地下温度（SUBT）异常信息作为耦合气候模式陆地分量的初始条件。主要的假设是，早春的LST和SUBT异常保存着春末和初夏即将融化的冻结地面的水丰度（即地面和以下冻结表面层的雪/冰量）的信息。地面及以下冰冻层的雪/冰越多，春季到夏季的季节过渡越长。西部高海拔地区这种季节转变的时机对东部低海拔地区下游环流格局的建立起了重要作用。其与陆海温差控制的低海拔地区环流型相互作用的强度和长度将影响大陆东部春夏后期干旱或洪涝的发生。本研究将利用不同气候和天气条件下的全球和区域模式进行各种数值模拟(i)了解LST/SUBT异常下游影响的机制，（ii）将其与海温异常的影响进行比较，（iii）识别和区分雪和土壤湿度在促进土壤记忆和保存LST/SUBT异常方面的作用。(4)探讨土层记忆与LST/SUBT异常特征及春季LST/SUBT异常的成因。该项目还将为业务模型开发一种新的SUBT初始化方法，以便更好地利用SUBT信息进行春夏季分季节/季节预报。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Impact of Initialized Land Surface Temperature and Snowpack on Subseasonal to Seasonal Prediction Project, Phase I (LS4P-I): organization and experimental design

• DOI: 10.5194/gmd-14-4465-2021
• 发表时间: 2021-07
• 期刊: Geoscientific Model Development
• 影响因子: 5.1
• 作者: Y. Xue;T. Yao;A. Boone;I. Diallo;Ye Liu;X. Zeng;W. Lau;S. Sugimoto;Q. Tang;Xiaoduo Pan;P. J. Oevelen;D. Klocke;Myung‐Seo Koo;Zhaohui Lin;Y. Takaya;Tomonori Sato;C. Ardilouze;S. Saha;Mei Zhao;Xin‐Zhong Liang;F. Vitart;Xin Li;P. Zhao;D. Neelin;W. Guo;Miao Yu;Y. Qian;S. Shen;Yang Zhang;Kun Yang;R. Leung;Jing Yang;Yuan Qiu;M. Brunke;S. Chou;M. Ek;T. Fan;H. Guan;Hai Lin;S. Liang;S. Materia;Tetsu Nakamura;Xin Qi;Retish Senan;C. Shi;Hailan Wang;Helin Wei;S. Xie;Haoran Xu;Hongliang Zhang;Yanling Zhan;Weiping Li;Xueli Shi;P. Nobre;Yi Qin;J. Dozier;C. Ferguson;G. Balsamo;Q. Bao;Jinming Feng;Jinkyu Hong;Songyoul Hong;Huilin Huang;D. Ji;Zhenming Ji;Shi-chang Kang;Yanluan Lin;Weiguang Liu;R. Muncaster;Yan Pan;D. Peano;P. Rosnay;Hiroshi G. Takahashi;Jianping Tang;G. Wang;Shuyu Wang;Weicai Wang;Xu Zhou;Yuejian Zhu

Modeling long-term fire impact on ecosystem characteristics and surface energy using a process-based vegetation–fire model SSiB4/TRIFFID-Fire v1.0

使用基于过程的植被火灾模型 SSiB4/TRIFFID-Fire v1.0 模拟火灾对生态系统特征和地表能量的长期影响

• DOI: 10.5194/gmd-13-6029-2020
• 发表时间: 2020
• 期刊: Geoscientific Model Development
• 影响因子: 5.1
• 作者: Huang, Huilin;Xue, Yongkang;Li, Fang;Liu, Ye
• 通讯作者: Liu, Ye

An assessment of potential climate impact during 1948–2010 using historical land use land cover change maps

使用历史土地利用土地覆盖变化图评估 1948 年至 2010 年期间的潜在气候影响

• DOI: 10.1002/joc.6621
• 发表时间: 2020
• 期刊: International Journal of Climatology
• 作者: Chilukoti, Nagaraju;Xue, Yongkang
• 通讯作者: Xue, Yongkang

Quantifying the major drivers for the expanding lakes in the interior Tibetan Plateau

量化青藏高原内陆湖泊扩张的主要驱动因素

• DOI: 10.1016/j.scib.2021.11.010
• 期刊: Science Bulletin
• 影响因子: 18.9
• 作者: Jing Zhou;Lei Wang;Xiaoyang Zhong;T;ong Yao;Jia Qi;Yuanwei Wang;Yongkang Xue
• 通讯作者: Yongkang Xue

Effects of spring Tibetan Plateau land temperature anomalies on early summer floods/droughts over the monsoon regions of South East Asia

• DOI: 10.1007/s00382-021-06053-8
• 发表时间: 2022-01
• 期刊: Climate Dynamics
• 影响因子: 4.6
• 作者: I. Diallo;Y. Xue;Qiu-shi Chen;X. Ren;W. Guo