Expected changes in future temperature extremes and their elevation dependency over the Yellow River source region

Abstract. Using the Statistical DownScaling Model (SDSM) and the outputs from two global climate models we investigate possible changes in mean and extreme temperature indices and their elevation dependency over the Yellow River source region for the period 2081–2100 under the IPCC SRES A2, A1B and B1 emission scenarios. Changes in interannual variability of mean and extreme temperature indices are also analyzed. The validation results show that SDSM performs better in reproducing the maximum temperature-related indices than the minimum temperature-related indices. The projections show that by the end of the 21st century all parts of the study region may experience increases in both mean and extreme temperature in all seasons, along with an increase in the frequency of hot days and warm nights and with a decrease in frost days. Interannual variability increases in all seasons for the frequency of hot days and warm nights and in spring for frost days while it decreases for frost days in summer. Autumn demonstrates pronounced elevation-dependent changes in which six out of eight indices show significant increasing changes with elevation.

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Expected changes in future temperature extremes and their elevation dependency over the Yellow River source region

Hydrology and Earth System Sciences ◽

10.5194/hess-17-2501-2013 ◽

2013 ◽

Vol 17 (7) ◽

pp. 2501-2514 ◽

Cited By ~ 11

Author(s):

Y. Hu ◽

S. Maskey ◽

S. Uhlenbrook

Keyword(s):

Interannual Variability ◽

21St Century ◽

Yellow River ◽

Source Region ◽

Extreme Temperature ◽

The Yellow River ◽

Hot Days ◽

Yellow River Source ◽

Temperature Indices ◽

Ipcc Sres

Abstract. Using the Statistical DownScaling Model (SDSM) and the outputs from two global climate models, we investigate possible changes in mean and extreme temperature indices and their elevation dependency over the Yellow River source region for the two future periods 2046–2065 and 2081–2100 under the IPCC SRES A2, A1B and B1 emission scenarios. Changes in interannual variability of mean and extreme temperature indices are also analyzed. The validation results show that SDSM performs better in reproducing the maximum temperature-related indices than the minimum temperature-related indices. The projections show that by the middle and end of the 21st century all parts of the study region may experience increases in both mean and extreme temperature in all seasons, along with an increase in the frequency of hot days and warm nights and with a decrease in frost days. By the end of the 21st century, interannual variability increases in all seasons for the frequency of hot days and warm nights and in spring for frost days while it decreases for frost days in summer. Autumn demonstrates pronounced elevation-dependent changes in which around six out of eight indices show significant increasing changes with elevation.

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Impacts of the Two Biggest Lakes on Local Temperature and Precipitation in the Yellow River Source Region of the Tibetan Plateau

Advances in Meteorology ◽

10.1155/2015/248031 ◽

2015 ◽

Vol 2015 ◽

pp. 1-10 ◽

Cited By ~ 11

Author(s):

Lijuan Wen ◽

Shihua Lv ◽

Zhaoguo Li ◽

Lin Zhao ◽

Nidhi Nagabhatla

Keyword(s):

Tibetan Plateau ◽

Yellow River ◽

Source Region ◽

Maximum Temperature ◽

The Yellow River ◽

The Tibetan Plateau ◽

Lake Area ◽

Local Climate ◽

Community Land Model ◽

Yellow River Source

The Tibetan Plateau harbors thousands of lakes; however few studies focus on impacts of lakes on local climate in the region. To investigate and quantify impacts of the two biggest lakes (Ngoring Lake and Gyaring Lake) of the Yellow River source region in the Tibetan Plateau on local climate, two simulations (with and without the two large lakes) from May 2010 to July 2011 are performed and analyzed using the WRF-CLM model (the weather research and forecasting model coupled with the community land model). Differences between simulated results show that the WRF-CLM model could provide realistic reproduction of surface observations and has better simulation after considering lakes. Lakes mostly reduce the maximum temperature all year round and increase the minimum temperature except in March due to the large heat capacity that makes lakes absorb (release) more energy for the same temperature change compared to land. Lakes increase precipitation over the lake area and in the nearby region, mostly during 02–14 BT (Beijing Time) of July to October when the warm lake surface induces the low level horizontal convergence and updraft over lake and provides energy and vapor to benefit the development of the convection for precipitation.

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Impacts of climate change on hydrology in the Yellow River source region, China

Journal of Water and Climate Change ◽

10.2166/wcc.2018.085 ◽

2018 ◽

Vol 11 (3) ◽

pp. 916-930 ◽

Cited By ~ 1

Author(s):

Junliang Jin ◽

Guoqing Wang ◽

Jianyun Zhang ◽

Qinli Yang ◽

Cuishan Liu ◽

...

Keyword(s):

Climate Change ◽

Yellow River ◽

Source Region ◽

Maximum Temperature ◽

Daily Minimum Temperature ◽

The Yellow River ◽

Vic Model ◽

Increasing Trend ◽

The Future ◽

Yellow River Source

Abstract Variations of precipitation, temperature, and runoff in the Yellow River source region were analyzed with the Mann–Kendall and Spearman rank correlation tests over the past 60 years. Based on the seven climate scenarios from CMIP5 climate models under RCP2.6, RCP4.5, and RCP8.5, responses of hydrological process to climate change were simulated using the Variable Infiltration Capacity (VIC) model. Variation analysis results indicated that recorded temperature presented significant increasing trend. Daily minimum temperature presented higher increasing trend than daily maximum temperature. Annual gross precipitation presented minor increasing and annual runoff presented minor decreasing. The VIC model performed well on simulating monthly discharge at Tangnaihai station, with NSE of 0.91 and 0.93 in calibration and validation periods, respectively. The projected annual mean temperature would rise (with 25th and 75th percentiles) 1.07–1.32 °C, 1.76–2.33 °C, 3.45–4.29 °C, annual precipitation is expected to increase 3.43%–11.77%, 8.05%–17.27%, 12.84%–27.89%, and runoff would moderately increase with high variability of 0.82%–14.26%, −3.41%–19.14%, 1.43%–38.26% relative to the baseline of 1961–1990 under each RCP in the 2080s, respectively. The inhomogeneity of runoff may increase in the future. Many more droughts and floods under climate change may threaten social development in this region in the future.

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Impact of Land Cover Types on Riverine CO2 Outgassing in the Yellow River Source Region

Water ◽

10.3390/w11112243 ◽

2019 ◽

Vol 11 (11) ◽

pp. 2243

Author(s):

Mingyang Tian ◽

Xiankun Yang ◽

Lishan Ran ◽

Yuanrong Su ◽

Lingyu Li ◽

...

Keyword(s):

Climate Change ◽

Land Cover ◽

Yellow River ◽

Stream Water ◽

Source Region ◽

The Yellow River ◽

Co2 Efflux ◽

Land Cover Types ◽

Yellow River Source ◽

Alpine Rivers

Under the context of climate change, studying CO2 emissions in alpine rivers is important because of the large carbon storage in these terrestrial ecosystems. In this study, riverine partial pressure of CO2 (pCO2) and CO2 emission flux (FCO2) in the Yellow River source region (YRSR) under different landcover types, including glaciers, permafrost, peatlands, and grasslands, were systematically investigated in April, June, August, and October 2016. Relevant chemical and environmental parameters were analyzed to explore the primary controlling factors. The results showed that most of the rivers in the YRSR were net CO2 source, with the pCO2 ranging from 181 to 2441 μatm and the FCO2 ranging from −50 to 1574 mmol m−2 d−1. Both pCO2 and FCO2 showed strong spatial and temporal variations. The highest average FCO2 was observed in August, while the lowest average was observed in June. Spatially, the lowest FCO2 were observed in the permafrost regions while the highest FCO2 were observed in peatland. By integrating seasonal changes of the water surface area, total CO2 efflux was estimated to be 0.30 Tg C year−1. This indicates that the YRSR was a net carbon source for the atmosphere, which contradicts previous studies that conclude the YRSR as a carbon sink. More frequent measurements of CO2 fluxes, particularly through several diel cycles, are necessary to confirm this conclusion. Furthermore, our study suggested that the riverine dissolved organic carbon (DOC) in permafrost (5.0 ± 2.4 mg L−1) is possibly derived from old carbon released from permafrost melting, which is equivalent to that in peatland regions (5.1 ± 3.7 mg L−1). The degradation of DOC may have played an important role in supporting riverine CO2, especially in permafrost and glacier-covered regions. The percent coverage of corresponding land cover types is a good indicator for estimating riverine pCO2 in the YRSR. In view of the extensive distribution of alpine rivers in the world and their sensitivity to climate change, future studies on dynamics of stream water pCO2 and CO2 outgassing are strongly needed to better understand the global carbon cycle.

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Research on valuation of water system in source region of the yellow river based on emergy theory

MATEC Web of Conferences ◽

10.1051/matecconf/201824601089 ◽

2018 ◽

Vol 246 ◽

pp. 01089

Author(s):

Yongqiang Wang ◽

Zhiming Liu ◽

Zhe Yuan ◽

Jijun Xu ◽

Jin Chen

Keyword(s):

Surface Water ◽

Water Resources ◽

Yellow River ◽

Source Region ◽

Source Area ◽

The Yellow River ◽

Energy Value ◽

Surface Water Resources ◽

Yellow River Source ◽

Value Of Water

Taking the source region of the Yellow River as an example, this paper first introduces the theory of energy value and its basic steps. Then combined with the Yellow River source area, the variation characteristics of precipitation and surface water resources from 1961 to 2011 in the Yellow River source area were analyzed, and both of them showed a trend of decreasing year by year. On this basis, using the theory of energy value, combined with relevant parameters, taking 2011 year as an example, further analyses the chemical energy and solar energy of water resources in the Yellow River source area, and gives the value of surface water resources. The value of water resources per unit is 1.59 yuan/m3. For the Yellow River source area, the overall value of water resources for the whole basin in 2011 is 33.55 billion yuan. It can provide a reference for the analysis of the value of surface water resources in the Yellow River Basin.

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