Fixes sign error in drdn_dRT in look_up_tables.py
@@ -267,7 +267,7 @@ class TabularRT:
K_surface = []
for i in range(len(x_surface)):
drho_drfl = \
- (transm/(1-sphalb*rfl)-(sphalb*transm*rfl)/pow(1-sphalb*rfl, 2))
+ (transm/(1-sphalb*rfl)+(sphalb*transm*rfl)/pow(1-sphalb*rfl, 2))
drdn_drfl = drho_drfl/s.pi*(self.solar_irr*self.coszen)
drdn_dLs = transup
K_surface.append(drdn_drfl * drfl_dsurface[:, i] +
