wiki:Evaluation/Fluxnet/r1118cwrr_corr

Version 2 (modified by nvuilsce, 12 years ago) (diff)

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r1118cwrr_corr

We diagnosed the reason why the results obtained with r1118 with CWRR are very different that those obtained with r1013_choisnel (see Ticket #91).
Indeed, the bare soil evaporation is very different between r1013_choisnel and r1118_cwrr. The vbeta4 term that is calculated differently in the 2 versions and that impacts on the evaporation calculation has also values that differ strongly bewteen r1013choisnel and r1118_cwrr.

As a test, an alternative simulation (to r1118_cwrr) has been done, in which vbeta4 is reduced by changing the following lines in hydrol.f90:

          IF ((evapot(ji).GT.min_sechiba) .AND. &
               (tmc_litter(ji,jst).GT.(tmc_litter_wilt(ji,jst)))) THEN
             evap_bare_lim_ns(ji,jst) = evap_bare_lim_ns(ji,jst) / evapot(ji)
          ELSEIF((evapot(ji).GT.min_sechiba).AND. &
               (tmc_litter(ji,jst).GT.(tmc_litter_res(ji,jst)))) THEN
             evap_bare_lim_ns(ji,jst) =  un/deux * evap_bare_lim_ns(ji,jst) / evapot(ji)
          END IF

by

	IF ((evapot(ji).GT.min_sechiba) THEN
             evap_bare_lim_ns(ji,jst) = 0.15*evap_bare_lim_ns(ji,jst) / evapot(ji)
	ENDIF	

This constitutes the simulation r1118cwrr_corr Overall, this simulation leads to a much better agreement with the observations, especially for DBF sites.

r1118cwrr_corr vs r1118cwrr

r1118cwrr_corr vs r1013choisnel