地理学报 ›› 2015, Vol. 70 ›› Issue (9): 1423-1433.doi: 10.11821/dlxb201509006

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20世纪末中国中东部耕地扩张对表面气温影响的模拟

张学珍1(), 刘纪远1, 熊喆2, 张宏文3   

  1. 1. 中国科学院地理科学与资源研究所 陆地表层格局与模拟院重点实验室,北京 100101
    2. 中国科学院大气物理研究所 东亚区域气候—环境院重点实验室,北京 100029
    3. 哈尔滨师范大学 黑龙江省普通高等学校地理环境遥感监测重点实验室,哈尔滨 150025
  • 收稿日期:2015-05-07 修回日期:2015-06-10 出版日期:2015-09-20 发布日期:2015-10-29
  • 作者简介:

    作者简介:张学珍(1981-), 博士, 副研究员, 主要从事地—气相互作用研究。E-mail: xzzhang@igsnrr.ac.cn

  • 基金资助:
    国家自然科学基金项目(41471171, 91425304);全球变化研究国家重大科学研究计划(2010CB950903);中国科学院青年创新促进会资助(2015038)

Simulated effects of agricultural development on surface air temperature over Central and Eastern China in the late 20th century

Xuezhen ZHANG1(), Jiyuan LIU1, Zhe XIONG2, Hongwen ZHANG3   

  1. 1. Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China
    2. Key Laboratory of Regional Climate?Environment for East?Asia, Institute of Atmospheric Physics, CAS, Beijing 100029, China
    3. Key Laboratory of Remote Sensing Monitoring of Geographic Environment, College of Heilongjiang Province, Harbin Normal University, Harbin 150025, China
  • Received:2015-05-07 Revised:2015-06-10 Online:2015-09-20 Published:2015-10-29
  • Supported by:
    National Natural Science Foundation of China, No.41471171, No.91425304;China Global Change Research Program, No.2010CB950903;Youth Innovation Promotion Association CAS, No.2015038

摘要:

利用WRF模式,通过4个21年(1980-2000年)的模拟实验,研究了20世纪末中国中东部耕地扩张对表面气温的影响。控制实验分析发现WRF模式能够捕捉温度场的空间格局,模拟与观测的季节平均温度场的相关系数为0.91~0.99(P < 0.001),但模拟温度比观测温度系统性偏低2~3 ℃。控制实验与敏感实验对比分析发现,东北区和中部区的毁林和毁草开荒具有降温效应,冬季平均降幅约为-0.41 ℃,居四季之首,主要是由地表反照率增加,净短波辐射减少,感热通量随之减少所致;东南区的毁林开荒具有升温效应,夏季温度升幅最大,平均升幅为0.14 ℃,主要原因是地表粗糙度减小,湍流减弱,热量在近地层集聚,难以扩散。农业扩张的升、降温效应主要出现在局地,对区域温度变化的影响甚微,一方面是因为农业扩张占区域面积份数甚小,另一方面是因为升、降温效应在区域平均过程中相互抵消。

关键词: 中国中东部, 农业扩张, WRF, 土地利用/覆盖变化(LUCC), 表面气温

Abstract:

We studied the effects of agricultural development on surface air temperature over Central and Eastern China in the late 20th century by performing four long-term (1980-2000) simulations using the Weather Forecast and Research (WRF) model. The four simulations used exactly the same settings except for the land use and land cover. One simulation referred as control simulation used the satellite-based land use and land cover data of the early 1980s. The other three simulations used the satellite-based land use and land cover data of 2000 only for Northeast, Central and Southeast China. By comparing the seasonal mean temperature of control simulation to ground measurement of 1981-1990, we found that WRF model had a cooling bias of about 2-3 ℃; however, WRF model well reproduced the spatial pattern of seasonal mean temperature with the correlation coefficient of 0.91-0.99 (P < 0.001). By comparing sensitive simulations with control simulation, we found that agriculture development resulted in significant changes of local temperature, but with large spatial differences and seasonal differences. In Northeast and Central China, the conversions from forest and grassland to cropland resulted in a cooling effect and the maximum cooling of about 0.41 ℃ occurred in winter. These land use conversions might enhance surface albedo and thereby reduced the surface net solar radiation; as a result, the surface sensible heat decreased and cooling occurred. In Southeast China, the conversion from forest to cropland led to a warming effect with the maximum being about 0.14 ℃ occurring in summer. The deforestation resulted in a flat surface and, thereby, turbulence was suppressed. Then, due to the suppressed turbulence, surface sensible heat was mostly used to heating bottom air rather than emitting into upper air. As a result, the surface climate warming occurred. The abovementioned cooling and warming effects induced by agriculture development could be comparable locally to the climate background changes. However, these cooling and warming effects had very weak modifications on regional mean temperature. This result implicates that the agriculture development-induced cooling and warming effects merely occurred in the locality and had little impacts on regional temperature changes.

Key words: Central and Eastern China, agricultural development, WRF model, land use and land cover changes (LUCC), surface air temperature