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Phil Harris , Chris Taylor, Rich Ellis Cat Luke, Tim Jupp. Land surface temperature and JULES. Outline. AMMA: convective initiation in West Africa SWELTER: European heat waves. AMMA: Sahel convective initiation.
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Phil Harris, Chris Taylor, Rich Ellis Cat Luke, Tim Jupp Land surface temperature and JULES
Outline AMMA: convective initiation in West Africa SWELTER: European heat waves
AMMA: Sahel convective initiation Initiations are associated with surface moisture variability on length scales ~10s km (Taylor and Ellis, 2006, GRL; Taylor et al 2011, Nature Geoscience) In situ boundary layer variability associated with surface moisture variability (Taylor et al, 2007, GRL; Taylor et al, 2009, QJRMS) What are the associated surface heat fluxes? No appropriate surface initial conditions for atmospheric model case studies of initiation
AMMA: LST assimilation ALMIP forcing on 0.5° grid Run JULES on MSG 3 km grid Assume LST errors due to precipitation amounts in forcing
AMMA: assimilation outputs Greatest corrections in the sparsely vegetated north
AMMA: assimilation outputs Fine-resolution (3 km) estimates of surface state and fluxes
AMMA: Atmospheric models These data used in forecast model case studies 4 km Unified Model Birch et al (submitted) QJRMS 0.5 km UKMO Large Eddy Model Dixon et al (submitted) QJRMS
SWELTER: European heat waves European heat waves may become more frequent Schär et al (2004) Nature
SWELTER: Modelled heat waves Standard forecast model Improved surface hydrology Weisheimer et al (2011) GRL Correlation between surface radiation and ET Std. dev. of the correlation across models Boé and Terray (2008) GRL
SWELTER Where and when is ET limited by soil moisture? Will soil moisture feedbacks increase the frequency of European summer droughts? Observations at 1 km Daily, 2001-2008 Model at 1 degree
SWELTER: Parameter estimation Use ADJULES to estimate model parameters Use parameters in UM projections
SWELTER: Pedo-transfer functions Wösten et al (1999)