Quantifying the contribution of land use change to surface temperature in the lower reaches of the Yangtze River

Abstract

Abstract. Anthropogenic land use has a significant impact on climate change. Located in the typical East Asian monsoon region, the land-atmosphere interaction in the lower reaches of the Yangtze River is even more complicated due to intensive human activities and different types of land use in this region. To better understand these effects on microclimate change, we compare differences in land surface temperature (T s ) for three land types around Nanjing from March to August, 2013, and then quantify the contribution of land surface factors to these differences ( T s ) by considering the effects of surface albedo, roughness length, and evaporation. The atmospheric background contribution to T s is also considered based on differences in air temperature ( T a ). It is found that the cropland cooling effect decreases T s by 1.76 • and the urban heat island effect increases T s by 1.25 • . They have opposite impacts but are both significant in this region. Various changes in surface factors affect radiation and energy distribution and eventually modify T s . It is the evaporative cooling effect that plays the most important role in this region and accounts for 1.40 • of the crop cooling and 2.29 • of the urban warming. Moreover, the background atmospheric circulation is also an indispensable part in land-atmosphere feedback induced by land use change and reinforces both these effects.

Urban Expansion and Drying Climate in an Urban Agglomeration of East China

“…First, the expansion in artificial built-up areas dramatically modifies the surface properties such as soil moisture, roughness, and albedo in urban areas (Myhre & Myhre, 2003;Wang et al, 2017;Yuzhen & Shunlin, 2018). First, the expansion in artificial built-up areas dramatically modifies the surface properties such as soil moisture, roughness, and albedo in urban areas (Myhre & Myhre, 2003;Wang et al, 2017;Yuzhen & Shunlin, 2018).…”

“…The mechanisms linking the UDI effect with the intensification of urban expansion are explained as follows. First, the expansion in artificial built‐up areas dramatically modifies the surface properties such as soil moisture, roughness, and albedo in urban areas (Myhre & Myhre, ; Wang et al, ; Yuzhen & Shunlin, ). Compared with rural areas, the impermeable built‐up surfaces (e.g., buildings, paved land, and motorways) in urban areas have less available soil moisture, thereby decreasing the atmospheric humidity above the ground.…”

Assessing the Impact of Urban Hydrological Processes on the Summertime Urban Climate in Nanjing Using the WRF Model

“…All verification is accomplished between the observations and the results of the grid cell where the site is located in the inner most model domain, where the grid spacing is 1 km × 1 km. Additional information about both the observations and sites can be found in previous studies (Guo et al, ; Wang et al, ; Zou et al, ).…”

Impact of Land Use/Land Cover Change on Surface Temperature Condition of Awka Town, Nigeria

“…The most significant of this change are variations in thermal characteristics of the area. Thus, built up areas tend to have land surface temperatures (LST) higher than surrounding suburban environment [8] [9]; and these thermal differences are contributing to the development of microclimatic condition otherwise referred to as the urban heat island (UHI) [1] [2] [10] [11]. Numerous studies [9]- [14] which have studied the relative effects of land use/Land cover change (LULCC) on LST have always found a positively correlated result with imperviousness.…”

“…More so, the removal of vegetation cover often leads to the adjustment in local water balance because the interception role of the canopy is lost, evapo-transpiration is changes or reduced [11] [15] runoff may be increased and radiation budget [2] may be upset by prescribing new surface geometry and albedo. These and numerous other effects reported in researches [1] [18] stressed the fact that man has very likely destroyed vegetation cover over vast areas for various purposes during the last few decades thereby leading to modification of climate [3] [19] as energy and mass balances are unfavourably altered, allowing the soil to be destroyed and desertification to set in most places.…”