Annual variations of monsoon and drought detected by GPS: A case study in Yunnan, China

The Global Positioning System (GPS) records monsoonal precipitable water vapor (PWV) and vertical crustal displacement (VCD) due to hydrological loading, and can thus be applied jointly to diagnose meteorological and hydrological droughts. We have analyzed the PWV and VCD observations during 2007.0–2015.0 at 26 continuous GPS stations located in Yunnan province, China. We also obtained equivalent water height (EWH) derived from the Gravity Recovery And Climate Experiment (GRACE) and precipitation at these stations with the same period. Then, we quantified the annual variations of PWV, precipitation, EWH and VCD and provided empirical relationships between them. We found that GPS-derived PWV and VCD (positive means downward movement) are in phase with precipitation and GRACE-derived EWH, respectively. The annual signals of VCD and PWV show linearly correlated amplitudes and a two-month phase lag. Furthermore, the results indicate that PWV and VCD anomalies can also be used to explore drought, such as the heavy drought during winter/spring 2010. Our analysis results verify the capability of GPS to monitor monsoon variations and drought in Yunnan and show that a more comprehensive understanding of the characteristics of regional monsoon and drought can be achieved by integrating GPS-derived PWV and VCD with precipitation and GRACE-derived EWH.

[1]  E. Small,et al.  Terrestrial water storage response to the 2012 drought estimated from GPS vertical position anomalies , 2014 .

[2]  M. Cheng,et al.  Deceleration in the Earth's oblateness , 2013 .

[3]  R. Bendick,et al.  Monsoonal loading in Ethiopia and Eritrea from vertical GPS displacement time series , 2015 .

[4]  Xavier Collilieux,et al.  Hydrological deformation induced by the West African Monsoon: Comparison of GPS, GRACE and loading models , 2012 .

[5]  W. Farrell Deformation of the Earth by surface loads , 1972 .

[6]  O. Francis,et al.  Modelling the global ocean tides: modern insights from FES2004 , 2006 .

[7]  Ecmwf Newsletter,et al.  EUROPEAN CENTRE FOR MEDIUM-RANGE WEATHER FORECASTS , 2004 .

[8]  Yibin Yao,et al.  GTm-III: a new global empirical model for mapping zenith wet delays onto precipitable water vapour , 2014 .

[9]  T. Herring,et al.  Introduction to GAMIT/GLOBK , 2006 .

[10]  B. Scanlon,et al.  GRACE satellite monitoring of large depletion in water storage in response to the 2011 drought in Texas , 2013 .

[11]  J. Kusche,et al.  Decorrelated GRACE time-variable gravity solutions by GFZ, and their validation using a hydrological model , 2009 .

[12]  B. Tapley,et al.  2005 drought event in the Amazon River basin as measured by GRACE and estimated by climate models , 2009 .

[13]  V. Tsai A model for seasonal changes in GPS positions and seismic wave speeds due to thermoelastic and hydrologic variations , 2011 .

[14]  S. Yirdaw,et al.  GRACE satellite observations of terrestrial moisture changes for drought characterization in the Canadian Prairie , 2008 .

[15]  Wu Chen,et al.  Thermal Effects on Vertical Displacement of GPS Stations in China , 2010 .

[16]  H. Schuh,et al.  Troposphere mapping functions for GPS and very long baseline interferometry from European Centre for Medium‐Range Weather Forecasts operational analysis data , 2006 .

[17]  Qiang Chen,et al.  Analyzing and modeling environmental loading induced displacements with GPS and GRACE , 2015 .

[18]  J. Wahr,et al.  A comparison of annual vertical crustal displacements from GPS and Gravity Recovery and Climate Experiment (GRACE) over Europe , 2007 .

[19]  Baolong Wang,et al.  Extreme drought changes in Southwest China from 1960 to 2009 , 2013, Journal of Geographical Sciences.

[20]  Jeffrey T. Freymueller,et al.  Seasonal and long-term vertical deformation in the Nepal Himalaya constrained by GPS and GRACE measurements , 2012 .

[21]  Jane Qiu,et al.  China drought highlights future climate threats , 2010, Nature.

[22]  Jing-shi Tang,et al.  Assessing the recent droughts in Southwestern China using satellite gravimetry , 2014 .

[23]  S. Bettadpur,et al.  Modeling Earth deformation from monsoonal flooding in Bangladesh using hydrographic, GPS, and Gravity Recovery and Climate Experiment (GRACE) data , 2010 .

[24]  A. Chulliat,et al.  International Geomagnetic Reference Field: the eleventh generation , 2010 .

[25]  Walter H. F. Smith,et al.  New, improved version of generic mapping tools released , 1998 .

[26]  M. Zhong,et al.  Contributions of thermal expansion of monuments and nearby bedrock to observed GPS height changes , 2009 .

[27]  Yibin Yao,et al.  Global empirical model for mapping zenith wet delays onto precipitable water , 2013, Journal of Geodesy.

[28]  Duncan Carr Agnew,et al.  Ongoing drought-induced uplift in the western United States , 2014, Science.

[29]  Felix W. Landerer,et al.  Seasonal variation in total water storage in California inferred from GPS observations of vertical land motion , 2014 .

[30]  The dry facts , 2013, Nature.

[31]  D. Alsdorf,et al.  Seasonal fluctuations in the mass of the Amazon River system and Earth's elastic response , 2005 .

[32]  Felix W. Landerer,et al.  GPS as an independent measurement to estimate terrestrial water storage variations in Washington and Oregon , 2015 .

[33]  Nico Sneeuw,et al.  Estimating Runoff Using Hydro-Geodetic Approaches , 2014, Surveys in Geophysics.

[34]  Yang Hong,et al.  Drought and flood monitoring for a large karst plateau in Southwest China using extended GRACE data , 2014 .

[35]  T. Herring,et al.  Correlation between changes in groundwater levels and surface deformation from GPS measurements in the San Gabriel Valley, California , 2012 .

[36]  D. Chambers,et al.  Estimating Geocenter Variations from a Combination of GRACE and Ocean Model Output , 2008 .

[37]  Y. Bock,et al.  Anatomy of apparent seasonal variations from GPS‐derived site position time series , 2001 .

[38]  Samuel Nahmani,et al.  West African Monsoon observed with ground-based GPS receivers during African Monsoon Multidisciplinary Analysis (AMMA) , 2008 .

[39]  T. Syed,et al.  Diagnosing Land Water Storage Variations in Major Indian River Basins using GRACE observations , 2015 .

[40]  Peter Steigenberger,et al.  Vertical deformations from homogeneously processed GRACE and global GPS long-term series , 2011 .

[41]  Peter J. Clarke,et al.  Subdaily signals in GPS observations and their effect at semiannual and annual periods , 2008 .

[42]  Steven Businger,et al.  GPS Meteorology: Mapping Zenith Wet Delays onto Precipitable Water , 1994 .