地理研究  2015 , 34 (10): 1853-1863 https://doi.org/10.11821/dlyj201510004

研究论文

WRF模拟的1980-2000年中国东北农业开发对气候的影响

张宏文1, 张学珍2, 张丽娟1

1. 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
2. 中国科学院地理科学与资源研究所,中国科学院陆地表层格局与模拟重点实验室,北京 100101

Simulated effects of cropland extension on climate over Northeast China from 1980 to 2000 by WRF Model

ZHANG Hongwen1, ZHANG Xuezhen2, ZHANG Lijuan1

1. Key Laboratory of Remote Sensing Monitoring of Geographic Environment, College of Heilongjiang Province, Harbin Normal University, Harbin 150025, China
2. Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China

通讯作者:  张学珍(1981- ),男,山东济宁人,副研究员,主要从事陆面过程与气候变化研究。E-mail: xzzhang@igsnrr.ac.cn

收稿日期: 2015-03-28

修回日期:  2015-08-10

网络出版日期:  2015-10-15

版权声明:  2015 《地理研究》编辑部 《地理研究》编辑部

基金资助:  国家自然科学基金项目(41471171,91325302,42171217)中国科学院青年创新促进会资助项目(2015038)江苏省气候变化协同创新中心资助项目

作者简介:

作者简介:张宏文(1990- ),男,黑龙江哈尔滨人,硕士研究生,主要从事陆面过程与气候变化研究。E-mail: zhw90419@163.com

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摘要

利用WRF模式,基于中国东北1980年代前期和2000年的土地利用/覆盖数据,分别进行了1980-2000年的气候变化模拟试验。通过两个试验结果的对比,分析了1980-2000年中国东北农业开发对气候的影响。在冬季和春季,农业开发使地表反照率增强,地表吸收的短波辐射减少,地表感热通量相应减少,地表气温降低;在夏季和秋季,农业开发削弱了地表反照率,地表吸收的短波辐射增加,同时地表潜热通量大幅增加,且增幅大于地表吸收的短波辐射的增幅,地表感热通量则相应减少,地表气温降低。农业开发的致冷幅度大多为0.1°C~1.0°C,与同期大尺度气候变化导致的当地背景温度变幅基本相当。农业开发引起的夏季降水变化因气候年景而异,“南旱北涝”年景下,呼伦贝尔—黑龙江省中部以及吉林省中部少雨,黑、吉、蒙三省(自治区)交界处降水增加,辽、蒙交界处以及辽东湾北部降水减少;“南涝北旱”年景下,呼伦贝尔—黑龙江省中部以及吉林省中部多雨,黑、吉、蒙三省(自治区)交界处降水减少,辽、蒙交界处以及辽东湾北部降水减少。农业开发的面积极其有限,因而由其导致的温度和降水显著变化主要出现在农业开发当地,尚不足以显著影响区域平均温度和降水变化。

关键词: WRF模式 ; 土地利用/覆盖变化 ; 地表气温 ; 夏季降水 ; 中国东北

Abstract

By using the land use/cover data for the early 1980 and 2000 in Northeast China, we carried out two 21-year (1980-2000) simulations, respectively, with the Weather Research and Forecast (WRF) model. This paper is aimed to investigate the effects of cropland extension on climate in Northeast China. In winter and spring, the replacement of natural grassland and forest by cropland enhanced land surface albedo, and surface net solar radiation was therefore reduced. As a consequence, the surface sensible heat flux decreased and the cooling effect occurred. Mostly, the local surface air temperature dropped by 0.1°C to 1.0°C. The cooling strength is comparable to the contemporaneous background temperature change which is induced by large circulation and sea surface temperature changes. In summer and autumn, the replacement of nature vegetation by cropland reduced land surface albedo, and surface net solar radiation was therefore increased. Meanwhile, the surface latent heat flux increased largely and the surface sensible heat flux decreased. As a result, there was also a cooling effect on local surface climate. These findings demonstrate detectable effects of land use/cover changes on local temperature. The effects of agricultural development on summer precipitation vary with background climate. In the South-Drought and North-Flood years, the decreased precipitation is detected in the Hulun Buir to central Heilongjiang province and central Jilin province and around the Liaodong Gulf while the precipitation increases in common boundary area of Heilongjiang, Jilin and Inner Mongolia. In the South-Flood and North-Drought years, the precipitation anomaly pattern is approximately reverse to the abovementioned South-Drought and North-Flood years with the exception that there is still decreased precipitation around the Liaodong Gulf. However, due to limited area with land use/cover changes, the impact on regional mean temperature is very limited.

Keywords: WRF model ; land use/cover change ; surface air temperature ; summer precipitation ; Northeast China

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张宏文, 张学珍, 张丽娟. WRF模拟的1980-2000年中国东北农业开发对气候的影响[J]. , 2015, 34(10): 1853-1863 https://doi.org/10.11821/dlyj201510004

ZHANG Hongwen, ZHANG Xuezhen, ZHANG Lijuan. Simulated effects of cropland extension on climate over Northeast China from 1980 to 2000 by WRF Model[J]. 地理研究, 2015, 34(10): 1853-1863 https://doi.org/10.11821/dlyj201510004

1 引言

陆地植被是气候系统中一个重要且多变的组成部分[1-5]。大量的科学证据表明植被覆盖变化将会引起当地或区域气候的改变[6,7]。植被覆盖通过改变地表反照率与地表净辐射以及感热、潜热和土壤热通量的分配比例来影响地表的能量平衡[8-10],或者通过改变地表粗糙度来调节大气中的水分及热量输送[11],从而影响和调节气候变化。从理解区域气候变化的角度来说,研究植被覆盖变化对气候的影响具有重要意义。

人类的农业开发是土地利用/覆盖变化的主要驱动力之一。东北地区是中国主要的农业生产基地,直至20世纪最后20年,该地区的农业仍处于扩张状态,耕地面积总体呈增加趋势,增加了306.24×104 hm2[12]。大规模农业开发为当地的社会经济发展和国家的粮食安全做出了重要贡献,但农业开发的代价是大、小兴安岭及东北中东部地区大面积林地和草地消失[12,13]。众所周知,20世纪最后20年全球气候变化以变暖为主要特征,地处中纬度北部的中国东北地区变暖幅度尤为突出。但是,毁林和垦牧拓耕对当地气候变暖的影响尚未得到深入研究,这不利于全面理解区域气候变化的动力机制,也不利于全面评估人类活动对区域气候变化的影响。

利用气候模式进行数值模拟试验是研究气候对外强迫变化响应的主要手段之一。目前,关于土地利用/覆盖变化的气候效应学术界开展了大量的模拟研究,大致可分为两类。一类是控制太阳辐射、CO2浓度等外强迫不变,利用不同时期的土地利用/覆盖数据进行模拟试验,将模拟的气候要素进行对比分析,揭示土地利用/覆盖变化对气候的影响。如高学杰等分别利用当前的和人类未开发前的土地利用/覆盖数据进行模拟试验,研究了人类的农业开发对中国区域气候的影响[14];Ge等利用1660年,1820年和2000年的土地利用/覆盖数据分别进行模拟试验,研究过去300年农业开垦对区域气候的影响[15]。另一类是使用定量遥感数据产品(如地表反照率、植被覆盖度等),替换模式中的原有相关数据,研究特定的地表物理参数变化对区域气候的影响。如张学珍等[16,17]分别利用MODIS的地表反照率产品和AVHRR的NDVI产品研究了地表反照率和植被覆盖度变化对中国气候的影响;潘小多等分析了天气研究和预报(Weather Research and Forecast,WRF)模式对土壤质地类型、地形高度等地表物理参数的敏感性[18]。第一类研究的对象是土地利用/覆盖类型的变化,通过土地利用/覆盖类型参数查算表将土地利用/覆盖变化信息“渗透入”模拟计算过程,查算表是模式研发者和用户设置的固定数值,优点是可以用于研究任意时期土地利用/覆盖类型变化的影响,缺点是模式从查算表获取的地表参数只因土地利用/覆盖类型而变,难以体现同一利用类型内部的差异。第二类研究是直接采用定量遥感产品,可以认为全面表征了地表的变化,其中既有土地利用/覆盖类型变化,也有同一利用类型内部的变化,比如,就耕地而言,由农业管理导致地表植被覆盖度等地表参数的变化,但是这类研究仅能用于研究有卫星观测以来的地表变化的影响。总而言之,20世纪末真实的中国东北大规模农业开发驱动的土地利用/覆盖类型变化对气候影响的模拟研究尚不多见。

本文利用WRF模式,针对中国东北地区,分别利用基于卫星遥感技术获取的1980 s前期和2000年的土地利用/覆盖数据,进行气候变化模拟试验,分析20世纪最后20年农业开发驱动的土地利用/覆盖变化对区域气候变化的影响,并对影响机制进行探讨,以期有利于提升关于中国东北地区气候变化动力机制的认识。

2 数据来源与研究方法

2.1 试验设计

采用美国国家大气科学中心(National Center for Atmospheric Research,NCAR)等机构联合研制的最新一代中尺度模式——WRF模式[19],该模式的应用领域由最初的中尺度天气预报逐渐拓展至区域气候模拟[20],并且在长期积分试验中表现出了较强的区域气候模拟能力[21]。近年来,WRF模式被广泛应用于中国地区的陆—气交互作用研究[22-24]。本文利用高级研究版的WRF,即ARW-WRF(V3.5)开展两组试验,一组是控制试验(简称CTL试验),采用1980 s前期的土地利用/覆盖,另一组试验(简称NE试验)则是在CTL试验的基础上将中国东北地区更新为2000年的土地利用/覆盖。除了土地利用/覆盖,两组试验采用完全相同的试验设置和物理过程参数化方案。模拟区域(虚线框范围)如图1所示,覆盖了整个东北地区,模拟区域中心点为(127.5°E,47°N),水平格距为30 km,格点数为154(东西)×168(南北),侧边界采用指数松弛方案,缓冲区为10个网格;垂直层数共有28层,模式顶层气压值为50 hPa。积分时间为1980年1月1日-2000年12月31日,采用6 h间隔的NCEP2再分析资料作为侧边界强迫场,模拟试验采用的主要物理过程参数化方案如下:WSM3简单冰微物理方案[25]、CAM3辐射方案、YSU边界层方案、Grell-Devenyi ensemble积云对流方案和Noah陆面过程方案[26]

图1   模拟区域范围(方框表示本文的研究区;灰度值表示地表海拔)

Fig. 1   The domain of simulation (The dashed box represents the study area; the gray represents elevation above sea level)

2.2 土地利用/覆盖数据

土地利用/覆盖数据由美国陆地卫星TM数据,辅以中巴资源卫星数据,解译得到[13,27]。数据的空间分辨率为1 km,采用中国土地利用分类体系(6个一级类型,25个二级类型),得到1 km×1 km像元内部各类土地类型的面积。WRF模式配置的是美国联邦地质调查局(USGS)定义的24类土地覆盖分类系统,网格大小为30 km×30 km。因而,本文采用表1所示的法则对土地利用/覆盖数据进行像元合并和类型转换。具体而言,对于存在“一对一”关系的类型,如果单一类型的面积占WRF网格面积超过一半,则直接将USGS体系的类型赋予该网格;对于“一对多”关系的类型,如果“多类”土地利用总面积占WRF网格面积超过一半,则直接将USGS体系的类型赋予该网格;对于“多对一”关系的类型,首先依据中国植被区划图[28]确定每个1 km像元内USGS体系的森林类型,如果单一类型森林占WRF网格面积超过一半,则直接将该森林类型赋予该网格。经过上述三步尚未获得赋值的网格,则按照表1中的法则赋值为混合类型。

表1   中国土地利用分类体系向USGS土地覆盖分类系统转换的法则(括号内的数字表示类型编码)

Tab. 1   The rules of conversion from Chinese land use classification to the USGS land cover classification(figure in the brackets denotes the code of land use/cover)

USGS分类体系中国土地利用分类体系
一对一旱作农业(2)旱地(12)
灌溉农业(3)水田(11)
灌丛(8)灌木林(22)
冰、雪(24)永久性冰川、雪地(44)
一对多城市与建筑用地(1)城镇用地(51)、农村居民点(52)、其他建设用地(53)
草地(7)高覆盖度(31)、中覆盖度(32)、低覆盖度(33)草地
水体(16)河渠(41)、湖泊(42)、水库(43)
禾本沼泽(17)滩涂(45)、滩地(46)、沼泽地(64)
裸地与稀疏植被(19)沙地(61)、戈壁(62)、盐碱地(63)、裸土地(65)、裸岩(66)、其他(67)
森林草原(10)疏林地(23)、其他林地(24)
多对一落叶阔叶林(11)有林地(21)
落叶针叶林(12)
常绿阔叶林(13)
常绿针叶林(14)
混合类型旱作/灌溉农业混合(4)旱地(12) 与水田(11) 占 WRF网格面积过半
混交林(15)有林地(21) 占WRF网格面积过半
农草混合(5)草地(31-33)和耕地(11-12) 占WRF网格面积最大
农林混合(6)林地(21-24)和耕地(11-12) 是WRF网格内前两类主导类型土地利用
灌草混合(9)林地(21-24)和草地(31-33) 是WRF网格内前两类主导类型土地利用

新窗口打开

经过上述预处理,在WRF模式网格框架下,东北地区土地利用/覆盖变化如图2所示。总计有148个网格的土地利用/覆盖发生变化,主要表现为林地、草地向农业用地的转变。其中,混合林向农林混合地转的网格数最多(38个),主要发生在东北平原的东部和北部;农牧混合地向旱地转变次之(20个),主要发生在东北平原的西部和南部;再次是农林混合地(16个)、森林草原(15个)开垦为旱地,以及森林草原(14个)、草地(11个)开垦为农牧混合地。这6类土地利用/覆盖变化总计为114个格点,占NE试验变化格点数的77.0%。

图2   东北地区土地利用/覆盖变化(仅显示变化的格点)

Fig. 2   The land use/cover change of Northeast China (Only changed grids are shown)

3 结果分析

3.1 控制试验模拟结果检验

为评价WRF模式模拟东北区域气候的能力,将CTL模拟的1981-1990年的逐季平均温度和夏季降水与地面观测的同期温度[29]及降水[30]进行对比。如图3所示,WRF模式能够再现东北地区温度和夏季降水空间分布的基本特征。WRF模式模拟的温度场与观测温度场的相关系数为0.91~0.97(P<0.001),其中夏季最大,冬季最小。模拟的夏季降水场与观测的同期降水场的相关系数为0.78(P<0.001)。但是模拟结果与观测数据之间也存在一定差异,对于温度场而言,二者的均方根误差为1.99°C~4.77°C,其中冬季最大,夏季最小,主要表现为模拟温度普遍低于观测值,即模拟气候偏冷,这是数值模式普遍存在的问题[14];对于夏季降水场而言,模拟与观测的均方根误差为0.73 mm/d,模拟误差主要表现为东北平原北部和小兴安岭地区模拟降水偏多,长白山南部模拟降水则偏少。

图3   CTL试验模拟1981-1990年的平均温度和夏季降水(上图)与地面观测的同期温度和降水(下图)

Fig. 3   Climatology temperature and summer precipitation of 1981-1990 from the CTL simulation and ground measurement respectively

WRF模式也刻画了夏季降水变化主导的空间特征。如图4所示,CTL模拟与观测数据的经验正交函数分解(EOF分析)均显示东北地区夏季降水变化的主要模态是南北反向,高变率中心分别位于黑龙江省的北部和辽东湾一带,空间格局的相关系数为0.70(P<0.001),时间系数的变化特征也基本一致,相关系数为0.53(P<0.02)。CTL模拟与观测的夏季降水的EOF分析的主要差异表现为:CTL模拟的第一模态方差解释量为22.74%,略高于观测数据17.97%的方差解释量。另外,1984-1985年观测数据并未展示出典型的南涝北旱特征,而CTL模拟展示了典型的南涝北旱特征。

图4   CTL试验模拟1981-2000年的夏季降水与地面观测同期降水的EOF第一模态及其时间系数

Fig. 4   The frist EOF model and time coefficient of 1981-2000 from the CTL simulation and ground measurement

造成模式模拟误差的原因有多种,比如边界数据的误差、模式动力学框架及物理过程参数化的不确定性。上述模拟误差是系统性的,在各模拟试验之间是共同存在的,本文不对模拟误差来源进行深入分析,而旨在通过对比分析模拟试验之间的差异,研究土地利用/覆盖变化的气候效应。

3.2 土地利用/覆盖变化导致的地表气温变化

20世纪末东北地区土地利用/覆盖变化对地表气温的影响如图5所示。地表气温的变化特征以降温为主,且主要出现在土地利用/覆盖变化的当地,温度变化绝大多数皆通过了0.05的显著性水平检验。其中冬、春两个季节的变化幅度相对较大,夏、秋两个季节的变化幅度相对较小。降温幅度较大地区主要集中在大兴安岭东部及东北平原西部地区,其他地区地表气温降幅相对较小。

图5   土地利用/覆盖变化对地表气温的影响(上图)及温度变化达到0.05显著性水平的格点(下图)

Fig. 5   The effect of the land use/cover change on seasonal daily mean surface air temperature (top panel) and significant grids at the level of 0.05 (bottom panel)

东北地区主要的6种土地利用/覆盖类型变化对地表气温的影响情况如表2所示。① 冬季,除农牧混合地开垦成旱地导致地表气温略微升高以外(0.08°C),其他5种土地利用/覆盖变化均引起地表气温下降,其中森林草原开垦为农牧混合地的降温幅度最大(-1.08°C),混合林开垦为农林混合地的降温幅度最小(-0.37°C);② 春季,除农牧混合地开垦为旱地导致地表气温略微升高外(0.08°C),其他5种土地利用/覆盖变化均引起地表气温的下降,其中森林草原开垦为农牧混合地的降温幅度最大(-0.87°C),混合林开垦为农林混合地的降温幅度最小(-0.13°C);③ 夏季,除混合林开垦为农林混合地导致地表气温升高以外(0.22°C),其他5种土地利用/覆盖变化均引起地表气温下降,其中草地开垦为农牧混合地的降温幅度最大(-0.26°C),森林草原开垦为农牧混合地降温幅度最小(-0.01°C);④ 秋季,除混合林开垦为农林混合地导致地表气温升高(0.16°C)和农牧混合地开垦为旱地没有引起地表气温明显变化以外(0°C),其他4种土地利用/覆盖变化均引起地表气温的下降,其中草地开垦为农牧混合地的降温幅度最大(-0.59°C),农林混合地开垦为旱地降温幅度最小(-0.18°C)。

表2   土地利用/覆盖变化导致的温度变化(括号外的数值)与背景温度变化(括号内的数值)(°C)

Tab. 2   Temperature change induced by land use/cover change (figures out of brackets) and the background temperature change (figures in brackets) (°C)

土地利用/覆盖变化冬季(12-2月)春季(3-5月)夏季(6-8月)秋季(9-11月)
混合林开垦为农林混合地-0.37(0.61)-0.13(-0.63)0.22(-0.13)0.16(0.10)
农牧混合地开垦为旱地0.08(0.25)0.08(-0.46)-0.04(0.11)0(0.03)
农林混合地开垦为旱地-0.54(0.47)-0.41(-0.63)-0.18(-0.06)-0.18(0.04)
森林草原开垦为旱地-0.99(0.09)-0.84(-0.57)-0.06(0.04)-0.52(-0.01)
森林草原开垦为农牧混合地-1.08(-0.02)-0.87(-0.44)-0.01(0.12)-0.57(-0.01)
草地开垦为农牧混合地-0.65(0.29)-0.50(-0.41)-0.26(0.14)-0.59(-0.02)

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进一步计算了CTL试验模拟得到的1991-2000年与1981-1990年平均温度之差,以此表征大尺度背景气候导致的温度变化(以下简称“背景温度变化”)。如表2所示,大多数土地利用/覆盖变化导致的局地温度变化与背景温度变化在量级上是可比的。东北地区,除了森林草原开垦为旱地和森林草原开垦为农牧混合地导致的秋季和冬季温度变化以及草地开垦为农牧混合地导致的秋季温度变化与背景温度变化的比率大于10(最大为57)以外,其余土地利用/覆盖变化导致的温度变化与背景温度变化均属于同一数量级,春、夏、秋和冬季前者与后者的平均比率分别是1.1、1.0、1.4和2.0。

3.3 土地利用/覆盖变化导致的夏季降水变化

考虑到不同年份夏季降水变化具有较大的空间差异(图4),依据EOF第一模态,本文分南涝北旱和南旱北涝两类年景分别研究土地利用/覆盖变化对降水的影响。年景的判断依据是CTL试验模拟的夏季降水量的EOF第一模态对应的时间系数,从大到小排序,时间系数最大的6年(1982年、1984年、1989年、1991年、1992年及1997年)为南旱北涝年,时间系数最小的6年(1985年、1986年、1994年、1995年、1998年及1999年)为南涝北旱年,该分类与观测数据分类较为一致。如图6所示,土地利用/覆盖变化导致的夏季降水变化因气候年景而异。“南旱北涝”年景下,北部盛行气旋型环流,850 hPa高度偏低,南部则盛行反气旋环流,850 hPa高度偏高(图6b),土地利用/覆盖变化导致呼伦贝尔—黑龙江省中部以及吉林省中部少雨,黑、吉、蒙三省(自治区)交界处降水增加,辽、蒙交界处以及辽东湾北部降水减少(图6e);“南涝北旱”年景下,北部盛行强大的反气旋,中心位于黑龙江省西部,850 hPa高度明显偏高,南部盛行相对偏弱的气旋,850 hPa高度略微偏高(图6d),土地利用/覆盖变化导致呼伦贝尔—黑龙江省中部以及吉林省中部多雨,黑、吉、蒙三省(自治区)交界处降水减少,辽、蒙交界处以及辽东湾北部降水减少(图6g)。

图6   东北地区夏季南旱北涝年景(a, b, e, f)和南涝北旱年景(c, d, g, h)下降水距平(a, c)、850 hpa高度场(彩色等值线图)和风场(箭头)距平(b, d)及土地利用/覆盖变化导致的降水量变化(e, g)和高度场(彩色等值线图)和风场变化(箭头)(f, h)

Fig. 6   Anomaly of summer precipitation (a, c) and geopotential height (color contours) and wind (arrows) at 850 hpa pressure level (b, d) and the changes in summer precipitation (e, g) and geopotential height (color contours) and wind (arrows) at 850 hpa pressure level (f,h) induced by Land use/cover changes (LUCC) in the South-Drought and North-Flood years (a, b, e, f) and South-Flood and North-Drought years (c, d, g, h) over Northeast China

3.4 地面辐射与能量收支及大气环流变化

地表辐射和能量支出分配是决定局地温度变化的主要因素。为了解释上述温度变化,本文分析了地表接收和反射的短波辐射,以及地表感热和潜热通量的变化。鉴于研究区内主要土地利用/覆盖类型导致的温度变化符号基本一致,本文计算了东北地区内土地利用/覆盖变化网格的平均值(表3)。如表3所示,冬春两季,地表净短波辐射均减少,减幅大致相当,分别为4.09 W/m2和4.30 W/m2,其主要原因是地表反照率增强,反射的短波辐射增加,增幅分别是4.52 W/m2和4.77 W/m2。作为对地表净短波辐射变化的响应,地表感热和潜热通量出现了不同程度的变化,其中地表感热降低幅度相对较大,分别为2.91 W/m2和5.69 W/m2,因而会产生制冷效应,由此解释了冬春两季地表气温的普遍降低。在夏秋两季,地表净短波辐射量有所增加,增加幅度分别为3.29 W/m2和0.42 W/m2,其原因主要是由于到达地表的短波辐射略有增加且地表反射的短波辐射有所减少。同时,地表感热通量减少和潜热通量增加,因而也会产生制冷效应,由此解释了地表气温在夏秋两季的普遍降低。

表3   CTL试验和NE试验地表辐射与能量收支变化(括号内的数值为CTL试验计算结果)

Tab. 3   The surface radiation and energy budget of NE simulation (figures out of brackets) and CTL simulation (figures in brackets)

到达地表的短波辐射(W/m2)地表反射的短波辐射(W/m2)地表净吸收短波辐射(W/m2)感热通量(W/m2)潜热通量(W/m2)地表气温(°C)
冬季
(12-2月)
116.44
(116.01)
69.69
(65.17)
46.75
(50.84)
-5.59
(-2.68)
2.94
(3.53)
-20.73
(-20.32)
春季
(3-5月)
264.59
(264.12)
102.43
(97.66)
162.16
(166.46)
36.5
(42.19)
41.9
(38.11)
-0.03
(0.27)
夏季
(6-8月)
233.1
(232.5)
42.76
(45.45)
190.34
(187.05)
32.36
(33.89)
88.95
(82.08)
18.01
(18.05)
秋季
(9-11月)
142.04
(141.64)
36.94
(36.96)
105.1
(104.68)
16.26
(16.91)
28.51
(27.34)
1.15
(1.32)

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降水变化与大气环流及其与之相关的水汽输送密切相关。土地利用/覆盖变化导致的风场和气压场变化因气候年景的不同而有明显差异。“南旱北涝”年景下,研究区北部的气旋减弱,东北地区由南至北盛行北风距平,不利于南风向北的水汽输送,这可能是降水普遍减少的主要原因(图6f)。“南涝北旱”年景下,内蒙古东部南风加强,加强了向北的水汽输送;吉林中部出现气旋距平,可能是吉林中部和黑龙江中部降水增加的主要原因;另外,辽东湾被高压距平笼罩,可能是该地区降水减少的主要原因(图6h)。

4 结论与讨论

研究表明,20世纪最后20年在东北地区发生的以毁林和垦牧为代价的农业开发,显著地改变了当地的地表辐射平衡和能量支出分配,进而产生了制冷效应,冬春季降幅大于秋季,夏季降幅最小。在冬季和春季,农业开发使地表反照率增强,地表吸收的短波辐射减少,地表感热通量相应减少,由此致冷;在夏季和秋季,农业开发削弱了地表反照率,地表吸收的短波辐射增加,但是地表潜热通量大幅增加,增幅大于地表吸收的短波辐射的增幅,地表感热通量则相应减少,由此致冷。冬春季局地降温幅度大多为0.1°C~1.0°C,这与同期背景温度变幅基本相当。这不同于过去300年农业开发导致区域变暖的研究结果[31],主要原因是过去300年农业开发主要是东北平原上由草地转变为耕地,而本研究时段主要是毁林开荒;另外,Zhang等[31]只研究了过去300年农业开发导致的地表反照率一个参数的变化,这也可能导致与本研究中多参数共同变化的影响结果不同。

东北地区农业开发导致的夏季降水变化因气候年景的不同而有明显差异。“南旱北涝”年景下,研究区北部的气旋减弱,东北地区由南至北盛行北风距平,不利于南风向北的水汽输送,导致呼伦贝尔—黑龙江省中部以及吉林省中部少雨,黑、吉、蒙三省(自治区)交界处降水增加,辽、蒙交界处以及辽东湾北部降水减少;“南涝北旱”年景下,内蒙古东部南风加强,加强了向北的水汽输送,吉林中部出现气旋距平,导致呼伦贝尔—黑龙江省中部以及吉林省中部多雨,黑、吉、蒙三省(自治区)交界处降水减少,辽、蒙交界处以及辽东湾北部降水减少。

本文通过数值模拟揭示了中国东北地区20世纪最后20年农业开发对当地气候变化的影响,支持了土地利用/覆盖变化能够显著影响局地气候的结论[32]。这意味着农业开发在冬季产生的显著致冷效应抑制了全球变暖背景下的局地变暖;换言之,如果没有农业开发,中国东北局部地区的变暖幅度可能比实测变暖幅度大。需要说明的是,土地利用/覆盖的影响仅限于当地。研究区域内仅有148个网格的土地利用/覆盖发生了变化,占东北区域总面积的7.16%,因而尚难以对区域气候变化产生显著影响。另外,如前所述,模式驱动数据和模式物理过程参数化方案均有一定的不确定性,因而本文的结果尚有一定的不确定性,需要进行更多模式模拟的对比和集合模拟,或者完善的地面观测数据的验证研究。

The authors have declared that no competing interests exist.


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. 地理学报, 2014, 69(1): 3-14.

https://doi.org/10.11821/dlxb201401001      URL      Magsci      [本文引用: 2]      摘要

土地利用/土地覆被变化(LUCC)是人类活动与自然环境相互作用最直接的表现形式,本文采用相同空间分辨率的卫星遥感信息源和相同的技术方法,对中国1980 年代末到2010 年土地利用变化数据进行定期更新。在此基础上,提出并发展土地利用动态区划的方法,研究土地利用变化的空间格局与时空特征。我们发现:1990-2010 年的20 年间,中国土地利用变化表现出明显的时空差异。“南减北增,总量基本持衡,新增耕地的重心逐步由东北向西北移动”是耕地变化的基本特征;“扩展提速,东部为重心,向中西部蔓延”是城乡建设用地变化的基本特征;“林地前减后增,荒漠前增后减,草地持续减少”是非人工土地利用类型变化的主要特征。20 世纪末与21 世纪初两个10 年相比,中国土地利用变化空间格局出现了一些新特征,原有的13 个土地利用变化区划单元演变为15 个单元,且部分区划单元边界发生变化。主要变化格局特征为黄淮海地区、东南部沿海地区、长江中游地区和四川盆地城镇工矿用地呈现明显的加速扩张态势;北方地区耕地开垦重心由东北地区和内蒙古东部转向西北绿洲农业区;东北地区旱作耕地持续转变为水田;内蒙古农牧交错带南部、黄土高原和西南山地退耕还林还草效果初显。近20 年间,尽管气候变化对北方地区的耕地变化有一定的影响,但政策调控和经济驱动仍然是导致我国土地利用变化及其时空差异的主要原因。2000 年后的第一个10 年,土地利用格局变化的人为驱动因素已由单向国土开发为主,转变为开发与保护并重。在空间格局变化的分析方法方面,应用“动态区划法”开展世纪之交两个10 年中国LUCC空间格局变化的分析,有效揭示了20 年来中国LUCC“格局的变化过程”,即动态区划边界的推移、区划单元内部特征的变化与单元的消长等;以及“变化过程的格局”,即土地利用变化过程与特征的分阶段区域差异,清晰刻画了LUCC动态区划中区划单元的消长,单元边界的变动,以及前后10 年的变化强度特征,揭示了土地利用“格局”与“过程”之间的交替转化规律,以及不同类型和区域的变化原因,证明了该分析方法的有效性。

[Liu Jiyuan, Kuang Wenhui, Zhang Zengxiang, et al.

Spatio-temporal characteristics, patterns and causes of land use changes in China since the late 1980s.

Acta Geographica Sinica, 2014, 69(1): 3-14.]

https://doi.org/10.11821/dlxb201401001      URL      Magsci      [本文引用: 2]      摘要

土地利用/土地覆被变化(LUCC)是人类活动与自然环境相互作用最直接的表现形式,本文采用相同空间分辨率的卫星遥感信息源和相同的技术方法,对中国1980 年代末到2010 年土地利用变化数据进行定期更新。在此基础上,提出并发展土地利用动态区划的方法,研究土地利用变化的空间格局与时空特征。我们发现:1990-2010 年的20 年间,中国土地利用变化表现出明显的时空差异。“南减北增,总量基本持衡,新增耕地的重心逐步由东北向西北移动”是耕地变化的基本特征;“扩展提速,东部为重心,向中西部蔓延”是城乡建设用地变化的基本特征;“林地前减后增,荒漠前增后减,草地持续减少”是非人工土地利用类型变化的主要特征。20 世纪末与21 世纪初两个10 年相比,中国土地利用变化空间格局出现了一些新特征,原有的13 个土地利用变化区划单元演变为15 个单元,且部分区划单元边界发生变化。主要变化格局特征为黄淮海地区、东南部沿海地区、长江中游地区和四川盆地城镇工矿用地呈现明显的加速扩张态势;北方地区耕地开垦重心由东北地区和内蒙古东部转向西北绿洲农业区;东北地区旱作耕地持续转变为水田;内蒙古农牧交错带南部、黄土高原和西南山地退耕还林还草效果初显。近20 年间,尽管气候变化对北方地区的耕地变化有一定的影响,但政策调控和经济驱动仍然是导致我国土地利用变化及其时空差异的主要原因。2000 年后的第一个10 年,土地利用格局变化的人为驱动因素已由单向国土开发为主,转变为开发与保护并重。在空间格局变化的分析方法方面,应用“动态区划法”开展世纪之交两个10 年中国LUCC空间格局变化的分析,有效揭示了20 年来中国LUCC“格局的变化过程”,即动态区划边界的推移、区划单元内部特征的变化与单元的消长等;以及“变化过程的格局”,即土地利用变化过程与特征的分阶段区域差异,清晰刻画了LUCC动态区划中区划单元的消长,单元边界的变动,以及前后10 年的变化强度特征,揭示了土地利用“格局”与“过程”之间的交替转化规律,以及不同类型和区域的变化原因,证明了该分析方法的有效性。
[13] 刘纪远, 张增祥, 庄大方, .

20世纪90年代中国土地利用变化时空特征及其成因分析

. 地理研究, 2003, 22(1): 1-12.

Magsci      [本文引用: 2]      摘要

<p>在土地利用变化时空信息平台的支持下,本文对我国20世纪80年代末到90年代末的土地利用变化过程进行了全面分析,揭示了我国10年来土地利用变化的时空规律,分析了这些规律形成的主要政策、经济和自然成因。研究表明,20世纪90年代,全国耕地总面积呈北增南减、总量增加的趋势,增量主要来自对北方草地和林地的开垦。林业用地面积呈现总体减少的趋势,减少的林地主要分布于传统林区,南方水热充沛区造林效果明显。中国城乡建设用地整体上表现为持续扩张的态势。90年代后5年总体增速减缓,西部增速加快。20世纪90年代我国的土地利用变化表现出明显的时空差异,政策调控和经济驱动是导致土地利用变化及其时空差异的主要原因。据此,本文提出在今后的全国土地利用规划中,应充分考虑我国现代土地利用变化的区域分异规律。同时,在生态环境恢复与建设规划中也应强调自然地理地带的针对性,同时要改变传统的资源规划与管理思路,在基础设施日益完备的条件下,最大程度地发挥跨区域土地资源优化配置的综合优势</p>

[Liu Jiyuan, Zhang Zengxiang, Zhuang Dafang, et al.

A study on the spatial-temporal dynamic changes of land-use and driving forces analyses of China in the 1990s.

Geographical Research, 2003, 22(1): 1-12.]

Magsci      [本文引用: 2]      摘要

<p>在土地利用变化时空信息平台的支持下,本文对我国20世纪80年代末到90年代末的土地利用变化过程进行了全面分析,揭示了我国10年来土地利用变化的时空规律,分析了这些规律形成的主要政策、经济和自然成因。研究表明,20世纪90年代,全国耕地总面积呈北增南减、总量增加的趋势,增量主要来自对北方草地和林地的开垦。林业用地面积呈现总体减少的趋势,减少的林地主要分布于传统林区,南方水热充沛区造林效果明显。中国城乡建设用地整体上表现为持续扩张的态势。90年代后5年总体增速减缓,西部增速加快。20世纪90年代我国的土地利用变化表现出明显的时空差异,政策调控和经济驱动是导致土地利用变化及其时空差异的主要原因。据此,本文提出在今后的全国土地利用规划中,应充分考虑我国现代土地利用变化的区域分异规律。同时,在生态环境恢复与建设规划中也应强调自然地理地带的针对性,同时要改变传统的资源规划与管理思路,在基础设施日益完备的条件下,最大程度地发挥跨区域土地资源优化配置的综合优势</p>
[14] 高学杰, 张冬峰, 陈仲新, .

中国当代土地利用对区域气候影响的数值模拟

. 中国科学: D辑, 2007, 37(3): 397-404.

https://doi.org/10.1007/s11442-007-0020-2      URL      [本文引用: 2]      摘要

使用RegCM3区域气候模 式,嵌套欧洲数值预报中心(ECMWF)ERA40再分析资料,分别进行了中国区域在实际植被和理想植被分布情况下各15年时间长度 (1987~2001)的积分试验,以探讨中国土地利用状况对气候的影响.通过两个试验结果的对比,研究了中国土地利用状况对气候的影响.分析主要集中于 气温和降水等变化上,并对结果进行了统计显著性检验.结果表明,当代土地利用/植被覆盖变化加强了中国地区冬、夏季的季风环流,同时改变了地表能量平衡状 况,从而对各气候要素产生重要影响.冬季,植被改变引起长江以南降水减少、气温降低,长江以北降水增加.夏季,植被改变显著影响了南方地区的气候,使得南 方降水增多,黄淮、江淮气温降低,华南气温上升;同时引起中国北方降水减少,气温在西北部分植被退化地区升高.植被变化对日最低、最高气温的影响更大.总 体而言,土地利用引起了年平均降水在南方增加、北方减少,年平均气温在南方显著降低.

[Gao Xuejie, Zhang Dongfeng, Chen Zhongxin, et al.

Land use effects on climate in China as simulated by a regional climate model.

Science in China: Series D, 2007, 37(3): 397-404.]

https://doi.org/10.1007/s11442-007-0020-2      URL      [本文引用: 2]      摘要

使用RegCM3区域气候模 式,嵌套欧洲数值预报中心(ECMWF)ERA40再分析资料,分别进行了中国区域在实际植被和理想植被分布情况下各15年时间长度 (1987~2001)的积分试验,以探讨中国土地利用状况对气候的影响.通过两个试验结果的对比,研究了中国土地利用状况对气候的影响.分析主要集中于 气温和降水等变化上,并对结果进行了统计显著性检验.结果表明,当代土地利用/植被覆盖变化加强了中国地区冬、夏季的季风环流,同时改变了地表能量平衡状 况,从而对各气候要素产生重要影响.冬季,植被改变引起长江以南降水减少、气温降低,长江以北降水增加.夏季,植被改变显著影响了南方地区的气候,使得南 方降水增多,黄淮、江淮气温降低,华南气温上升;同时引起中国北方降水减少,气温在西北部分植被退化地区升高.植被变化对日最低、最高气温的影响更大.总 体而言,土地利用引起了年平均降水在南方增加、北方减少,年平均气温在南方显著降低.
[15] Ge Q S, Zheng J Y, Zhang X Z, et al.

Simulated effects of cropland expansion on summer climate in eastern China in the last three centuries.

Advances in Meteorology, 2013, 65(2): 93-100.

https://doi.org/10.1155/2013/501014      URL      [本文引用: 1]      摘要

To understand the effects of the land use/cover changes due to agricultural development on summer climate in Eastern China, four 12-year simulations using the WRF-SSiB model were performed. We found that agricultural development resulted in warming and rainy effects. In the middle to lower reaches of the Yellow River and the Yangtze River, the warming effects were approximately 0.6掳C and resulted from increased surface net radiation and sensible heat fluxes. In Northeast China, the warming effects were very small due to increases in latent heat fluxes which resulted from the extensive conversion from grassland to cropland. The rainy effect resulted from increases in convective rainfall, which was associated with a warming surface in certain areas of the Yellow River and Yangtze River and a large increase in the surface moisture flux in Northeast China. Conversely, in the middle to lower reaches of the Yellow River and the Yangtze River, the grid-scale rainfall decreased because the climatological northward wind, which is moist and warm, was partially offset by a southward wind anomaly. These findings suggest that the agricultural development left footprints not only on the present climate but also on the historical climate changes before the industrial revolution. 1. Introduction Eastern China is affected by the Asian monsoon [1]. In this area, summer is the warmest and wettest season. The heat and rainfall in summer feed agriculture for human welfare. Therefore, the summer climate has crucial implications to the origination
[16] 张学珍, 郑景云, 何凡能, .

MODIS BRDF/Albedo数据在中国温度模拟中的应用

. 地理学报, 2011, 66(3): 356-366.

Magsci      [本文引用: 1]      摘要

地表反照率直接影响地表辐射平衡,进而改变当地温度(2 m气温,下同),然后还可能通过大气平流过程影响下游地区的温度。为揭示利用实时更新的地表反照率替换WRF (Weather Research and Forecasting) 模式的静态地表反照率对中国大陆温度模拟结果的影响,本文进行了两组为期6 年(2002-2007 年) 的连续积分试验:控制试验(CT试验) 采用短波波段地表反照率,取自WRF模式推荐的地表参数数据集;敏感试验(MD试验) 采用分波段的(可见光和近红外) 地表反照率,取自MODIS BRDF/Albedo数据产品。试验结果表明,CT试验能够模拟中国温度的基本空间格局,但是模拟温度相对于观测温度有明显偏差,青藏高原南部的模拟温度偏低(负偏差),最大偏低幅度为1.03oC,出现在秋季,东部地区的模拟温度偏高(正偏差),最大偏高幅度达3.4oC,出现在春季;MD试验模拟结果的正、负偏差格局与CT试验基本相似,但是与CT试验相比,MD试验模拟的青藏高原南部温度的负偏差更大,最大为1.32oC,而模拟的东部地区温度的正偏差明显减小,最大为2.97oC,这说明MD试验比CT试验模拟的温度普遍偏低。在青藏高原,这主要归因于MD试验比CT试验的地表反照率大,使得地表净辐射少,地表感热少,致使温度偏低;在中国东部的黄淮海至江南丘陵区,这主要归因于MD试验中北方蒙古高原的地表反照率比CT试验的大,使得MD试验中该地区的地表净辐射少,地表感热少,温度低,然后通过南下冷平流过程致使位于其下游的黄淮海至江南丘陵区温度降低。

[Zhang Xuezhen, Zheng Jingyun, He Fanneng, et al.

Application of MODIS BRDF/Albedo dataset in the regional temperature simulation of China.

Acta Geographica Sinica, 2011, 66(3): 356-366.]

Magsci      [本文引用: 1]      摘要

地表反照率直接影响地表辐射平衡,进而改变当地温度(2 m气温,下同),然后还可能通过大气平流过程影响下游地区的温度。为揭示利用实时更新的地表反照率替换WRF (Weather Research and Forecasting) 模式的静态地表反照率对中国大陆温度模拟结果的影响,本文进行了两组为期6 年(2002-2007 年) 的连续积分试验:控制试验(CT试验) 采用短波波段地表反照率,取自WRF模式推荐的地表参数数据集;敏感试验(MD试验) 采用分波段的(可见光和近红外) 地表反照率,取自MODIS BRDF/Albedo数据产品。试验结果表明,CT试验能够模拟中国温度的基本空间格局,但是模拟温度相对于观测温度有明显偏差,青藏高原南部的模拟温度偏低(负偏差),最大偏低幅度为1.03oC,出现在秋季,东部地区的模拟温度偏高(正偏差),最大偏高幅度达3.4oC,出现在春季;MD试验模拟结果的正、负偏差格局与CT试验基本相似,但是与CT试验相比,MD试验模拟的青藏高原南部温度的负偏差更大,最大为1.32oC,而模拟的东部地区温度的正偏差明显减小,最大为2.97oC,这说明MD试验比CT试验模拟的温度普遍偏低。在青藏高原,这主要归因于MD试验比CT试验的地表反照率大,使得地表净辐射少,地表感热少,致使温度偏低;在中国东部的黄淮海至江南丘陵区,这主要归因于MD试验中北方蒙古高原的地表反照率比CT试验的大,使得MD试验中该地区的地表净辐射少,地表感热少,温度低,然后通过南下冷平流过程致使位于其下游的黄淮海至江南丘陵区温度降低。
[17] Ge Q S, Zhang X Z, Zheng J Y.

Simulated effects of vegetation increase/decrease on temperature changes from 1982 to 2000 across the Eastern China.

International Journal of Climatology, 2014, 34(1): 187-196.

https://doi.org/10.1002/joc.3677      Magsci      [本文引用: 1]      摘要

<p>The local/regional temperature changes were significantly regulated by land surface changes. This study aims to reveal the effects of vegetation increase/decrease on temperature changes from 1982 to 2000 across the Eastern China. To reach this goal, we performed two 20-year simulations, dynamical vegetation experiment (DYCV) and fixed vegetation experiment (FIXV), with the coupled Weather Research and Forecast (WRF)-Noah model. The DYCV used the essential satellite-measured vegetation variations from 1982 to 2000 while FIXV kept the vegetation properties in 1982 for the entire simulation. The results show that vegetation increase/decrease exerted negative effects locally and the effects were stronger in growth season than that in non-growth season. From 1982 to 2000, in the areas where vegetation increased, such as North China Plain for the spring and south part of Northeast China for the summer and autumn, climate warming was slowed; whereas, in the areas where vegetation decreased, such as Yangtze River Delta and Pearl River Delta for the summer, climate warming was enhanced. Such negative effect was resulted from changes in partition of surface net radiation between surface latent heat and sensible heat. Increased vegetation caused more evaportranspiration and thus more latent heat and less sensible heat; it is reverse for the decreased vegetation. In comparing, changes in surface net radiation were too slight to be detected. Noted that, due to flaws of coupled WRF-Noah model, the results for the summer and winter have some uncertainties and needed to be verified with more studies. Copyright &copy; 2013 Royal Meteorological Society</p>
[18] 潘小多, 李新, 冉有华, .

下垫面对WRF模式模拟黑河流域区域气候精度影响研究

. 高原气象, 2012, 31(3): 657-667.

Magsci      [本文引用: 1]      摘要

利用高精度的土地覆盖、 土壤质地类型和地形高度值替换了天气研究和预报模式Weather Research and Forecasting Model (WRF)中的相关数据, 通过数值模式试验检验了下垫面数据对WRF模拟精度的影响。同时, 通过与黑河综合遥感联合试验中7个测站观测数据的比较, 以平均误差、 均方根误差和相关系数为指标, 分析了WRF模式下垫面数据改变对近地表气象要素的模拟精度的影响。结果表明: (1)WRF模式本身的地形高度信息在黑河流域上游地区有较大误差, 造成了一定的模拟误差。而使用高精度的下垫面数据可以提高WRF模式在黑河流域上游复杂区域的模拟能力; (2)2 m气温除了随地形高度递减外, 还受土壤质地和土地覆盖小幅度影响,&nbsp; 而且进行地形订正后的2 m气温与2 m湿度的模拟在下垫面为水体的区域对比强烈, 因此为模式提供准确的水体分布信息也至关重要; (3)2 m气温和湿度等要素的模拟差异值与地形高度资料的差异呈负相关, 而降雨量的差异与地形高度差异呈微弱的正相关, 与土壤质地差异和土地覆盖差异的相关性也比较弱。

[Pan Xiaoduo, Li Xin, Ran Youhua, et al.

Impact of underlying surface information on WRF modeling in Heihe river basin.

Plateau Meteorology, 2012, 31(3): 657-667.]

Magsci      [本文引用: 1]      摘要

利用高精度的土地覆盖、 土壤质地类型和地形高度值替换了天气研究和预报模式Weather Research and Forecasting Model (WRF)中的相关数据, 通过数值模式试验检验了下垫面数据对WRF模拟精度的影响。同时, 通过与黑河综合遥感联合试验中7个测站观测数据的比较, 以平均误差、 均方根误差和相关系数为指标, 分析了WRF模式下垫面数据改变对近地表气象要素的模拟精度的影响。结果表明: (1)WRF模式本身的地形高度信息在黑河流域上游地区有较大误差, 造成了一定的模拟误差。而使用高精度的下垫面数据可以提高WRF模式在黑河流域上游复杂区域的模拟能力; (2)2 m气温除了随地形高度递减外, 还受土壤质地和土地覆盖小幅度影响,&nbsp; 而且进行地形订正后的2 m气温与2 m湿度的模拟在下垫面为水体的区域对比强烈, 因此为模式提供准确的水体分布信息也至关重要; (3)2 m气温和湿度等要素的模拟差异值与地形高度资料的差异呈负相关, 而降雨量的差异与地形高度差异呈微弱的正相关, 与土壤质地差异和土地覆盖差异的相关性也比较弱。
[19] Skamarock W C, Klemp J B, Dudhia J, et al.

A Description of the Advanced Research WRF Version 3

. Boulder, Coloradoi: NCAR/TN-475+STR, 2008.

URL      [本文引用: 1]      摘要

The development of the Weather Research and Forecasting (WRF) modeling system is a multiagency effort intended to provide a next-generation mesoscale forecast model and data assimilation system that will advance both the understanding and prediction of mesoscale weather and accelerate the transfer of research advances into operations. The model is being developed as a collaborative effort ort among the NCAR Mesoscale and Microscale Meteorology (MMM) Division, the National Oceanic and Atmospheric Administration's (NOAA) National Centers for Environmental Prediction (NCEP) and Forecast System Laboratory (FSL), the Department of Defense's Air Force Weather Agency (AFWA) and Naval Research Laboratory (NRL), the Center for Analysis and Prediction of Storms (CAPS) at the University of Oklahoma, and the Federal Aviation Administration (FAA), along with the participation of a number of university scientists. The WRF model is designed to be a flexible, state-of-the-art, portable code that is an efficient in a massively parallel computing environment. A modular single-source code is maintained that can be configured for both research and operations. It offers numerous physics options, thus tapping into the experience of the broad modeling community. Advanced data assimilation systems are being developed and tested in tandem with the model. WRF is maintained and supported as a community model to facilitate wide use, particularly for research and teaching, in the university community. It is suitable for use in a broad spectrum of applications across scales ranging from meters to thousands of kilometers. Such applications include research and operational numerical weather prediction (NWP), data assimilation and parameterized-physics research, downscaling climate simulations, driving air quality models, atmosphere-ocean coupling, and idealized simulations (e.g boundary-layer eddies, convection, baroclinic waves).
[20] Leung L R, Kuo Y H, Tribbia J.

Research needs and directions of regional climate modeling using WRF and CCSM.

Bulletin of the American Meteorological Society, 2006, 87(12): 1747-1751.

https://doi.org/10.1175/BAMS-87-12-1747      URL      [本文引用: 1]      摘要

Climate varies across a wide range of temporal and spatial scales. Yet, climate modeling has long been approached using global models that can resolve only the broader scales of atmospheric processes and their interactions with land, ocean, and sea ice. Clearly, large-scale climate determines the environment for mesoscale and microscale processes that govern the weather and local climate, but, likewise, processes that occur at the regional scale may have significant impacts on the large scale circulation. Resolving such scale interactions will lead to much improved understanding of how climate both influences, and is influenced by, human activities. Since October 2003, the National Center for Atmospheric Research (NCAR) has supported an effort through the Opportunity Fund to develop regional climate modeling capability using the Weather Research and Forecasting (WRF) model (http://www.wrf-model.org/index.php) and the Community Climate System Model (CCSM) (http://www.ccsm.ucar.edu/models), with participations by members of both the Mesoscale and Microscale Meteorology and Climate and Global Dynamics Divisions. The goal is to develop a next generation community Regional Climate Model (RCM) that can address both downscaling and upscaling issues in climate modeling. Downscaling is the process of deriving regional climate information based on large-scale climate conditions. Both dynamical and statistical downscaling methods have more 禄 been used to produce regional climate change scenarios; however, their resolution and physical fidelity are considered inadequate. Hence, the global change community has expressed a strong demand for improved regional climate information to explore the implications of adaptation and mitigation and assess climate change impacts (http://www.climatescience.gov/events/workshop2002/). Upscaling encapsulates the aggregate effects of small-scale physical and dynamical processes on the large-scale climate. One form of upscaling is the use of physical parameterizations such as that for deep conve
[21] Leung L R, Qian Y.

Atmospheric rivers induced heavy precipitation and flooding in the western U.S. simulated by the WRF regional climate model.

Geophysical Research Letters, 2009, 36(3): 1-6.

https://doi.org/10.1029/2008GL036445      URL      [本文引用: 1]      摘要

[1] A 20-year regional climate simulated by the Weather Research and Forecasting model has been analyzed to study the influence of the atmospheric rivers and land surface conditions on heavy precipitation and flooding in the western U.S. The simulation realistically captured the mean and extreme precipitation, and the precipitation/temperature anomalies of all the atmospheric river events between 1980&ndash;1999. Contrasting the 1986 President Day and 1997 New Year Day events, differences in atmospheric stability have an influence on the spatial distribution of precipitation. Although both cases yielded similar precipitation, the 1997 case produced more runoff. Antecedent soil moisture, rainfall versus snowfall, and existing snowpack all seem to play a role, leading to a higher runoff to precipitation ratio for the 1997 case. This study underscores the importance of the atmospheric rivers and land surface conditions for predicting heavy precipitation and floods in the current and future climate of the western U.S.
[22] 史小康, 文军, 田辉, .

MODIS反照率产品在模拟黄河源区陆面过程和降水中的应用

. 大气科学, 2009, 33(6): 1187-1200.

https://doi.org/10.3878/j.issn.1006-9895.2009.06.06      Magsci      [本文引用: 1]      摘要

地表反照率是陆面过程中一个重要的物理量, 其变化直接影响地表能量的收支状况, 进而可以影响气温和降水等其它气象要素。本文利用WRF (Weather Research and Forecasting) 模式, 通过两组数值模拟试验分别探讨了地表反照率改变在黄河源区不同下垫面情况下潜热、 感热的分配关系, 详细分析了地表反照率改变对降水变化的影响机制, 最后应用EOS/MODIS地表反照率产品替代原模式低时空分辨率的地表反照率。研究结果表明: (1)当地表反照率减少(增加)时, 模拟的区域平均地表温度、感热、潜热数值相应增大(减少)。当地表反照率减少0.1时, 地表温度上升约1.0 K, 感热和潜热量增量比约为3∶1。 (2) 地表反照率改变对降水量变化影响最大的区域是黄河源区下游的草场区域, 其次是黄河源头区域, 最小的是黄河源区北部的稀疏植被区域。地表反照率通过对大气动力、 热力以及水汽条件的影响, 使得降水发生的环境改变, 主要体现在: 当地表反照率减少时, 地表气压的减少使得大气低层的辐合气流增强, 有利于上升运动的发生; 2.0 m气温的升高增强了大气近地层的热力不稳定度; 2.0 m比湿的增加表明近地层空气水汽含量增加。 (3) 与实况对比分析发现, 使用卫星遥感产品后在月尺度上能够更准确地模拟降水量的变化过程。

[Shi Xiaokang, Wen Jun, Tian Hui, et al.

Application of MODIS albedo data in the simulation of land surface and rainfall processes over the Yellow River water source region.

Chinese Journal of Atmospheric Sciences, 2009, 33(6): 1187-1200.]

https://doi.org/10.3878/j.issn.1006-9895.2009.06.06      Magsci      [本文引用: 1]      摘要

地表反照率是陆面过程中一个重要的物理量, 其变化直接影响地表能量的收支状况, 进而可以影响气温和降水等其它气象要素。本文利用WRF (Weather Research and Forecasting) 模式, 通过两组数值模拟试验分别探讨了地表反照率改变在黄河源区不同下垫面情况下潜热、 感热的分配关系, 详细分析了地表反照率改变对降水变化的影响机制, 最后应用EOS/MODIS地表反照率产品替代原模式低时空分辨率的地表反照率。研究结果表明: (1)当地表反照率减少(增加)时, 模拟的区域平均地表温度、感热、潜热数值相应增大(减少)。当地表反照率减少0.1时, 地表温度上升约1.0 K, 感热和潜热量增量比约为3∶1。 (2) 地表反照率改变对降水量变化影响最大的区域是黄河源区下游的草场区域, 其次是黄河源头区域, 最小的是黄河源区北部的稀疏植被区域。地表反照率通过对大气动力、 热力以及水汽条件的影响, 使得降水发生的环境改变, 主要体现在: 当地表反照率减少时, 地表气压的减少使得大气低层的辐合气流增强, 有利于上升运动的发生; 2.0 m气温的升高增强了大气近地层的热力不稳定度; 2.0 m比湿的增加表明近地层空气水汽含量增加。 (3) 与实况对比分析发现, 使用卫星遥感产品后在月尺度上能够更准确地模拟降水量的变化过程。
[23] Zhang X Z, Tang Q H, Zheng J Y, et al.

Warming/cooling effects of cropland greenness changes during 1982-2006 in the North China Plain.

Environmental Research Letters, 2013, 8(2): 1-9.

https://doi.org/10.1088/1748-9326/8/2/024038      URL      摘要

) change in spring and ~19% in early summer. The cooling?wetting/warming?drying effects mainly resulted from the distinct partitioning of surface net radiation between surface latent heat flux and sensible heat flux over cropland with different greenness. Canopy transpiration plays a dominant role. The increased (decreased) cropland greenness corresponds to high (low) transpiration rate, less (more) sensible heat flux and high (low) humidity, and consequently cooling?wetting (warming?drying) effects. In comparison, there was little change in surface net radiation, although surface albedo and emissivity had changed with greenness change.
[24] Jeong S J, Ho C H, Piao S, et al.

Effects of double cropping on summer climate of the North China Plain and neighbouring regions.

Nature Climate Change, 2014, 4(7): 615-619.

URL      [本文引用: 1]     

[25] Hong S Y, Dudhia J, Chen S H.

A revised approach to ice microphysical processes for the bulk parameterization of clouds and precipitation.

Monthly Weather Review, 2004, 132(1): 103-120.

https://doi.org/10.1175/1520-0493(2004)1322.0.CO;2      URL      [本文引用: 1]      摘要

A revised approach to cloud microphysical processes in a commonly used bulk microphysics parameterization and the importance of correctly representing properties of cloud ice are discussed. Several modifications are introduced to more realistically simulate some of the ice microphysical processes. In addition to the assumption that ice nuclei number concentration is a function of temperature, a new and separate assumption is developed in which ice crystal number concentration is a function of ice amount. Related changes in ice microphysics are introduced, and the impact of sedimentation of ice crystals is also investigated. In an idealized thunderstorm simulation, the distribution of simulated clouds and precipitation is sensitive to the assumptions in microphysical processes, whereas the impact of the sedimentation of cloud ice is small. Overall, the modifications introduced to microphysical processes play a role in significantly reducing cloud ice and increasing snow at colder temperatures and slightly increasing cloud ice and decreasing snow at warmer temperatures. A mesoscale simulation experiment for a heavy rainfall case indicates that impact due to the inclusion of sedimentation of cloud ice is not negligible but is still smaller than that due to the microphysics changes. Together with the sedimentation of ice, the new microphysics reveals a significant improvement in high-cloud amount, surface precipitation, and large-scale mean temperature through a better representation of the ice cloud芒鈧鈥渞adiation feedback.
[26] Yang Z L, Niu G Y, Mitchell K E, et al.

The community Noah land surface model with multiparameterization options (Noah-MP): 2. Evaluation over global river basins.

Journal of Geophysical Research, 2011, 116(D12): 1-16.

https://doi.org/10.1029/2010JD015140      URL      [本文引用: 1]      摘要

[1] The augmented Noah land surface model described in the first part of the two‐part series was evaluated here over global river basins. Across various climate zones, global‐scale tests can reveal a model's weaknesses and strengths that a local‐scale testing cannot. In addition, global‐scale tests are more challenging than local‐ and catchment‐scale tests. Givenconstant model parameters (e. g., runoff parameters) across global river basins, global‐scale tests are more stringent. We assessed model performance against various satellite andground‐based observations over global river basins through six experiments that mimic a transition from the original Noah LSM to the fully augmented version. The model shows transitional improvements in modeling runoff, soil moisture, snow, and skin temperature, despite considerable increase in computational time by the fully augmented Noah‐MPversion compared to the original Noah LSM. The dynamic vegetation model favorablycaptures seasonal and spatial variability of leaf area index and green vegetation fraction. We also conducted 36 ensemble experiments with 36 combinations of optional schemes forrunoff, leaf dynamics, stomatal resistance, and the b factor. Runoff schemes play a dominant and different role in controlling soil moisture and its relationship with evapotranspiration compared to ecological processes such as the b factor, vegetation dynamics, and stomatal resistance. The 36‐member ensemble mean of runoff performs better than any singlemember over the world's 50 largest river basins, suggesting a great potential of land‐based ensemble simulations for climate prediction.
[27] 刘纪远, 刘明亮, 庄大方, .

中国近期土地利用变化的空间格局分析

. 中国科学: D辑, 2002, 32(12): 1031-1041.

https://doi.org/10.3321/j.issn:1006-9267.2002.12.008      URL      [本文引用: 1]      摘要

在全球环境变化研究中,土地利用和土地覆被动态越来越被认为是一个关键而迫切的研究课题,依据覆盖中国1990年代末期5a时间间隔的陆地卫星数据资料,研究了土地利用变化的特征和空间分布规律,依据土地利用动态度的概念,在1km格网土地利用变化数据基础上,根据区域近期土地利用动态特点与社会,自然环境综合特征,设计了全国土地利用动态区划图,揭示了土地利用变化过程的空间格局,总体上,传统农作区(包括黄淮海平原,长江三角洲地区和四川盆地等)城镇居民建设用地的扩张侵占了大面积的耕地,而北方农牧交错带与西北绿洲农业区由于生产条件,经济利益和气候变化等方面的原因,耕地开垦现象最为突出,国家退耕还林还草政策的实施效果在局部地区有所体现,但截至2000年,尚未对土地覆被变化产生区域性的影响,此5a期间森林砍伐现象依然比较严峻,本项研究,实现了中国现代土地利用动态区域单元的划分,揭示了中国现代土地利用变化的时间-空间属性并为其特征分析提供了区域格局框架,该项研究是地理科学对研究对象的“空间格局”与“时间过程”特征进行集成研究,揭示研究对象“变化过程的格局”,“以及格局的变化过程”的一次有益的尝试。

[Liu Jiyuan, Liu Mingliang, Zhuang Dafang, et al.

Spatial pattern analysis of recent land-use change in China.

Science in China: Series D, 2002, 32(12): 1031-1041.]

https://doi.org/10.3321/j.issn:1006-9267.2002.12.008      URL      [本文引用: 1]      摘要

在全球环境变化研究中,土地利用和土地覆被动态越来越被认为是一个关键而迫切的研究课题,依据覆盖中国1990年代末期5a时间间隔的陆地卫星数据资料,研究了土地利用变化的特征和空间分布规律,依据土地利用动态度的概念,在1km格网土地利用变化数据基础上,根据区域近期土地利用动态特点与社会,自然环境综合特征,设计了全国土地利用动态区划图,揭示了土地利用变化过程的空间格局,总体上,传统农作区(包括黄淮海平原,长江三角洲地区和四川盆地等)城镇居民建设用地的扩张侵占了大面积的耕地,而北方农牧交错带与西北绿洲农业区由于生产条件,经济利益和气候变化等方面的原因,耕地开垦现象最为突出,国家退耕还林还草政策的实施效果在局部地区有所体现,但截至2000年,尚未对土地覆被变化产生区域性的影响,此5a期间森林砍伐现象依然比较严峻,本项研究,实现了中国现代土地利用动态区域单元的划分,揭示了中国现代土地利用变化的时间-空间属性并为其特征分析提供了区域格局框架,该项研究是地理科学对研究对象的“空间格局”与“时间过程”特征进行集成研究,揭示研究对象“变化过程的格局”,“以及格局的变化过程”的一次有益的尝试。
[28] 张新时. 中华人民共和国植被图(1:100万). 北京: 地质出版社, 2007.

[本文引用: 1]     

[Zhang Xinshi. Vegetation Map of the People's Republic of China (1:1000000). Beijing: Geological Publishing House, 2007.]

[本文引用: 1]     

[29] Xu Y, Gao X J, Shen Y, et al.

A daily temperature dataset over China and its application in validating a RCM simulation.

Advances in Atmospheric Sciences, 2009, 26(4): 763-772.

https://doi.org/10.1007/s00376-009-9029-z      Magsci      [本文引用: 1]      摘要

<a name="Abs1"></a>This paper describes the construction of a 0.5° × 0.5° daily temperature dataset for the period of 1961&#8211;2005 over mainland China for the purpose of climate model validation. The dataset is based on the interpolation from 751 observing stations in China and comprises 3 variables: daily mean, minimum, and maximum temperature. The &#8220;anomaly approach&#8221; is applied in the interpolation. The gridded climatology of 1971&#8211;2000 is first calculated and then a gridded daily anomaly for 1961&#8211;2005 is added to the climatology to obtain the final dataset. Comparison of the dataset with CRU (Climatic Research Unit) observations at the monthly scale shows general agreement between the two datasets. The differences found can be largely attributed to the introduction of observations at new stations. The dataset shows similar interannual variability as does CRU data over North China and eastern part of the Tibetan Plateau, but with a slightly larger linear trend. The dataset is employed to validate the simulation of three extreme indices based on daily mean, minimum, and maximum temperature by a high-resolution regional climate model. Results show that the model reproduces these indices well. The data are available at the National Climate Center of China Meteorological Administration, and a coarser resolution (1° × 1°) version can be accessed via the World Wide Web.
[30] Xie P P, Yatagai A, Chen M Y, et al.

A gauge-based analysis of daily precipitation over East Asia.

Journal of Hydrometeorology, 2007, 8(3): 607-626.

https://doi.org/10.1175/JHM583.1      URL      [本文引用: 1]      摘要

中国科学院机构知识库(中国科学院机构知识库网格(CAS IR GRID))以发展机构知识能力和知识管理能力为目标,快速实现对本机构知识资产的收集、长期保存、合理传播利用,积极建设对知识内容进行捕获、转化、传播、利用和审计的能力,逐步建设包括知识内容分析、关系分析和能力审计在内的知识服务能力,开展综合知识管理。
[31] Zhang X Z, Wang W C, Fang X Q, et al.

Agriculture development-induced surface albedo changes and climatic implications across northeastern China.

Chinese Geographical Science, 2012, 22(3): 264-277.

https://doi.org/10.1007/s11769-012-0535-z      Magsci      [本文引用: 2]      摘要

Abstract<br/><p class="a-plus-plus">To improve the understandings on regional climatic effects of past human-induced land cover changes, the surface albedo changes caused by conversions from natural vegetation to cropland were estimated across northeastern China over the last 300 years, and its climatic effects were simulated by using the Weather Research and Forecasting (WRF) model. Essential natural vegetation records compiled from historical documents and regional optimal surface albedo dataset were used. The results show that the surface albedo decreased by 0.01–0.03 due to conversions from grassland to cropland in the Northeast China Plain and it increased by 0.005–0.015 due to conversions from forests to cropland in the surrounding mountains. As a consequence, in the Northeast China Plain, the surface net radiation increased by 4–8 W/m<sup class="a-plus-plus">2</sup>, 2–5 W/m<sup class="a-plus-plus">2</sup>, and 1–3 W/m<sup class="a-plus-plus">2</sup>, and the climate was therefore warmed by 0.1°C–0.2°C、0.1°C–0.2°C、 0.1°C–0.3° in the spring, autumn and winter, respectively. In the surrounding mountain area, the net radiation d °C ecreased by less than 1.5 W/m<sup class="a-plus-plus">2</sup>, and the climate was therefore cooled too slight to be detected. In summer, effects of surface albedo changes on climate were closely associated with moisture dynamics, such as evapotranspiration and cloud, instead of being merely determined by surface radiation budget. The simulated summer climatic effects have large uncertainties. These findings demonstrate that surface albedo changes resulted in warming climate effects in the non-rainy seasons in Northeast China Plain through surface radiation processes while the climatic effects in summer could hardly be concluded so far.</p><br/>
[32] Pitman A J, Arneth A, Ganzeveld L.

Regionalizing global climate models.

International Journal of Climatology, 2012, 32(3): 321-337.

https://doi.org/10.1002/joc.2279      URL      [本文引用: 1]      摘要

Global climate models simulate the Earth's climate impressively at scales of continents and greater. At these scales, large-scale dynamics and physics largely define the climate. At spatial scales relevant to policy makers, and to impacts and adaptation, many other processes may affect regional and local climate and perhaps trigger teleconnections that provide significant feedbacks on the global climate. These processes include fire, irrigation, land cover change (including crops and urban landscapes), and the emissions of biogenic volatile organic compounds by vegetation. Many of these interact within the atmosphere via dynamical, physical, and chemical mechanisms that lead to boundary-layer feedbacks. It is unlikely that any of these processes have a significant global-scale impact on the Earth's climate in the sense that the amount of warming due to a doubling of well mixed greenhouse gases would change if these processes were explicitly represented in climate models. These phenomena are usually local in space (e.g. urban) or in time (e.g. fire) and probably do not provide the on-going and sustained forcing to affect the global climate. However, for most impacts and adaptation research it is the regional and local climate that defines climate risk. At these scales, processes missing in climate models can have a substantially larger local-scale impact than the additional radiative forcing due to increasing greenhouse gases. Thus, while climate models are well designed for global and continental scales they exclude a suite of important processes that are locally and/or regionally important. We review these missing processes and highlight the research required to resolve the representation of these regional-scale processes in climate models. We also discuss the experimental methodology required to rigorously determine whether these processes are restricted to a local or regional-scale role or whether they do trigger robust teleconnections that would demonstrate global-scale significance

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