Evaluation of Groundwater Sustainability in Selected Regions of China and Future Projection under Climate Change

Background• Groundwater is a limited resource.• Human activities such as pumping and irrigation need large amounts of groundwater supply.• Current Available Estimates of Global Groundwater Storage and Groundwater Flux in Literature are of High Uncertainty.

Study Area

Discussion• Categorization of RGS

ü Variable Stress, Unstressed, Overstress, Human-dominated Stressü Stress scale for variable stress

• Possible causes of difference for GW depletion ü Over-estimation of specific yieldü Under-estimation of GW depletion due to model errors in GLDASü Other sources of GW: South-North Water Transfer Project (~5.7mm/year)

• Comparison with other indices (i.e. Total Groundwater Stress)• Further improvement on how to derive Renewable Groundwater Stress in time series instead of a time-averaged value• Recommendations on the limit of pumping based on groundwater stress

Data Validation

Source Total groundwater storage (106 km3)

Mean groundwater flux (103 km3/year)

L’Vovich (1967, 1974) 60.0 12.0FAO (2003) N.A. 11.284Wada et al. (2010) N.A. 15.2Richey et al. (2015) 7.0 - 23.0 N.A.

Data availability

GRACEresolution (~200,000

km3)

More serious

problem in Northern

China

Three study

aquifers chosen

North China Plain Aquifer(~140,000 km2)

Songliao Basin (~350,000 km2)

Tarim Basin (~560,000 km2)

Internally:Three outputs of GRACE and four outputs of GLDAS are consistent for time span 2005 to 2015.

Externally (take thecomparison withprecipitation as anexample):The peaks of TWS is delayed half an month to one monthcompared with the peaks of precipitation.

NCP (mm/year) Songliao Basin (mm/year)

Tarim Basin (mm/year)

PCR-GLOBWB model (Wada, 2010) (Recharge a)

17.25 12.77 14.77

China Water Resources (2005)

111.16 69.24 37.81

Average of PCR-GLOBWB model and China Water Resources bulletin (Recharge b)

64.21 41.01 26.29

Richey et al. (2015b) 96.56 20.16 -0.74

Aquifer name Depletion rate

(mm/year)

NCP -8.83

Songliao Basin 7.13

Tarim Basin 1.16

Aquifer name Depletion rate

(mm/year)

NCP -8.86

Songliao Basin 3.67

Tarim Basin 0.972

Results

Aquifer name Depletion rate

(mm/year)

NCP -7.19

Songliao Basin 3.15

Tarim Basin 0.636

Richey et

al. (2015b)

NCP -0.514 -0.417 -0.138 -0.112 -0.08

Songliao Basin 0.287 0.247 0.089 0.077 0.12

Tarim Basin 0.066 0.043 0.037 0.024 0.32

Richey, A. S., Thomas, B. F., Lo, M.-H., Reager, J. T., Famiglietti, J. S., Voss, K., Swenson, S. and Rodell, M. (2015b). Quantifying renewable groundwater stress with GRACE. Water Resources Research, 51. Doi:10.1002/2015WR017349. Huang Z., Y. Pan, H. Gong, P. J.-F. Yeh, X. Li, D. Zhou, W. Zhao, 2015, Subregional-scale groundwater depletion detected by GRACE from both shallow and deep aquifers in the North China Plain, Geophysical Research Letters, 42, doi:10.1002/2014GL062498.

Department of Civil and Environmental EngineeringStudent Name: Zhou Yimin Email: zhouyimin0810@gmail.com Matric No: A0105556H