Coherent lake growth on the central Tibetan Plateau since the 1970s: Characterization and attribution Yanbin Lei a,⇑ , Tandong Yao a , Broxton W. Bird a,b , Kun Yang a , Jianqing Zhai c , Yongwei Sheng d a Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, China b Department of Earth Sciences, Indiana University–Purdue University Indianapolis (IUPUI), Indianapolis, IN 46202, USA c National Climate Center, China Meteorological Administration, Beijing 100081, China d Department of Geography, University of California, Los Angeles (UCLA), Los Angeles, CA 90405, USA article info Article history: Received 14 September 2012 Received in revised form 26 December 2012 Accepted 6 January 2013 Available online 12 January 2013 This manuscript was handled by Konstantine P. Georgakakos, Editor-in-Chief, with the assistance of Daqing Yang, Associate Editor Keywords: Lake growth Tibetan Plateau Climatic change Glacier mass loss Lake level variation summary Although lakes on the central Tibetan Plateau (TP) expanded significantly in recent decades, causes for the lake growth still have not been well addressed. Based on remote sensing and GIS techniques together with bathymetric survey and water balance analysis, we show how climatic changes and glacier mass loss have influenced the inland lake dynamics on the central TP. Our results show that six closed lakes (Siling Co, Nam Co, Bam Co, Pung Co, Darab Co and Zige Tangco) expanded by 20.2% in area, by 8.7 m in water depth, and by 37.7 Gt in the total storage between 1976 and 2010, with a remarkable acceler- ation after 1999. The growth rate of lake area, water level and storage between 1999 and 2010 was 5.0, 3.6 and 4.8 times, respectively, than that between 1976 and 1999, corresponding well with the sig- nificant climatic changes in the late 1990s. Water balance analysis shows that increased precipitation and runoff, and decreased lake evaporation were the main causes for the coherent lake growth and could con- tribute by about 70% of total increase in lake storage. Based on modern mass balance results , glacier mass loss between 1999 and 2010 was estimated to contribute to the lake level rise of the three glacial-fed lakes, Siling Co, Nam Co and Pung Co, by 1.0 m, 0.7 m and 1.1 m, respectively, accounting for 11.7%, 28.7% and 11.4% of the total lake level rise. Ó 2013 Elsevier B.V. All rights reserved. 1. Introduction The Tibetan Plateau (TP) is a major geographic feature with an area of over 2.5  10 6 km 2 and an average elevation of more than 4000 m above sea level (a.s.l.). During recent decades, TP has been experiencing significant changes, e.g. rising surface air tempera- ture (Wang et al., 2008), the weakening of atmospheric heat source (Duan and Wu, 2008; Yang et al., 2011a), the decrease in wind speed, solar radiation and potential evaporation (Zhang et al., 2007, 2009). Meteorological data show that mean annual temper- ature increased at a rate of 0.36 °C/decade on the TP over the per- iod of 1951–2007 (Wang et al., 2008), which is more than twice the rate of the north hemisphere (Solomon et al., 2007). Due to the in- crease in water vapor amount and deep cloud cover, solar radiation across the TP decreased (Yang et al., 2012). Rising temperature in- creased land evaporation, however, potential evaporation de- creased due to the wind stilling and solar dimming. This complementary relationship between potential evaporation and actual evaporation is proposed by Bouchet (1963), and is applica- ble on the TP (Yang et al., 2011b). The TP boasts the greatest concentration of high-altitude inland lakes in the world. Recent estimates indicate that there are more than 1000 lakes over 1 km 2 distributed on the TP, with a total area of 41,800 km 2 (Ma et al., 2010). With a total area of 100,000 km 2 , glaciers on the TP and surroundings play an impor- tant role in the discharge of headwaters of many Asian rivers (Yao et al., 2012). Although there is some spatial variability (Bolch et al., 2012; Gardelle et al., 2012), most of the glaciers on the TP have experienced significant melting and retreating in recent decades (Yao et al., 2004, 2007, 2012). In contrast, lakes on the central TP have expanded rapidly since the late 1990s (Liu et al., 2009; Bian et al., 2010; Meng et al., 2011; Zhang et al., 2011a,b). Because many lakes on the TP contain gla- ciers in their catchment, it has been hypothesized that increase in glacial meltwater has contributed significantly to the growth of inland lakes (Zhu et al., 2010; Yao et al., 2007, 2010). However, many lakes without glacial supply in their catchments have also expanded significantly in recent decades, which indicates that other climatic changes such as increased precipitation and de- creased lake evaporation may also have contributed to the recent lake growth (Morrill, 2004; Liu et al., 2009). In this study, we first 0022-1694/$ - see front matter Ó 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.jhydrol.2013.01.003 ⇑ Corresponding author. Address: Building 3, Courtyard 16, Lincui Road, Chaoy- ang District, Beijing 100101, China. Tel./fax: +86 10 62849886. E-mail address: leiyb@itpcas.ac.cn (Y. Lei). Journal of Hydrology 483 (2013) 61–67 Contents lists available at SciVerse ScienceDirect Journal of Hydrology journal homepage: www.elsevier.com/locate/jhydrol