000004266 001__ 4266
000004266 005__ 20190902132814.0
000004266 037__ $$aCTALK-2019-0122
000004266 100__ $$aDelobbe, L.
000004266 245__ $$aHeavy rainfall estimates from underground gravity measurements
000004266 260__ $$c2019
000004266 269__ $$c2019-09-12
000004266 520__ $$aEstimation of rainfall amounts produced by convective storms is challenging due to the very high spatial variabilityof such type of precipitation. In this study we explore the use of underground gravity monitoring to estimate heavyrainfall at a spatial scale of a few hundred meters.Superconducting  gravimeters  produce  gravity  measurements  with  a  precision  of  1  nm/s2at  1-minute  timestep. When performed underground, these measurements are directly affected by rainfall. Water mass increase atthe ground level due to precipitation tends to reduce underground gravity. Rainfall amounts can be derived fromthese gravity variations.The  superconducting  gravimeters  used  in  this  study  are  installed  in  Membach  (Belgium)  and  Walferdange(Luxembourg),  48 m  and  80  m  underneath  the  surface,  respectively.  The  gravimeters  integrate  soil  water  in  aradius  of  several  hundred  meters.  The  two  gravimeters  are  located  at  85  and  54  km  from  a  C-band  weatherradar located in Wideumont (Belgium). Gravimeter data at 1-min time step and radar data at 5-min time step areavailable for the 15-year observation period 2003-2017.The  comparison  of  radar  reflectivity  and  gravity  time  series  shows  that  short-duration  intense  rainfall  eventsproduce  a  rapid  decrease  of  the  underground  measured  gravity.  Precipitation  amounts  derived  from  gravitymeasurements  and  from  radar  observations  are  further  compared  for  more  than  500  events  with  very  intenseprecipitation over short durations.We  show  that  a  superconducting  gravimeter  is  a  valuable  source  of  in-situ  observations  for  the  verificationof rainfall estimates derived from weather radars. The two main benefits are the spatial scale at which precipitationis captured and the interesting property that gravity measurements are directly influenced by water mass at groundno matter the type of precipitation: hail or rain.
000004266 594__ $$aNO
000004266 6531_ $$aWeather radar
000004266 6531_ $$aMembach
000004266 6531_ $$aWalferdange
000004266 6531_ $$aSuperconducting gravimeter
000004266 700__ $$aFrancis, O.
000004266 700__ $$aWatlet, A.
000004266 700__ $$aVan Camp, M.
000004266 773__ $$tEMS Annual Meeting 2019
000004266 8560_ $$fmichel.vancamp@observatoire.be
000004266 85642 $$ahttps://www.ems2019.eu/home.html
000004266 906__ $$aContributed
000004266 980__ $$aCTALKCONT