Changes between Version 5 and Version 6 of user/clem/Heat_Flux_air-ice-ocean_interface
- Timestamp:
- 2016-04-15T17:33:06+02:00 (8 years ago)
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user/clem/Heat_Flux_air-ice-ocean_interface
v5 v6 10 10 11 11 So far, as an input from the atmosphere, NEMO only had Qns. Therefore NEMO had to make a guess on Qsnow, Qrain and Qevap by considering the temperature of falling snow, rain and evaporated water = SST, and temperature of evaporated ice = 0°C. Then,[[BR]] 12 (''O Marti'' : when it's snowing on sea ice, using the surface temperature (snow/ice) would be a better first guess. But the actual flux from ATM is still needed to be conservative) 13 ''C Rousset'': I agree but I do not think we have access to ice surface temperature at this stage (not sure though)?12 >(''O Marti'' : when it's snowing on sea ice, using the surface temperature (snow/ice) would be a better first guess. But the actual flux from ATM is still needed to be conservative)[[BR]] 13 >>''C Rousset'': I agree but I do not think we have access to ice surface temperature at this stage (not sure though)? 14 14 15 15 {{{Qsnow = sprecip * ice_frac * ( Cp * SST - Lfus ) [in W/m2]}}} … … 22 22 23 23 with sprecip = snow precip, lprecip = liquid precip, ice_frac = ice fraction, Cp = specific heat of sea water, Lfus = Latent heat of fusion of pure ice at 0deg, SST = sea surface temperature.[[BR]] 24 ''A Voldoire'' : Concerning {{{Qrain = lprecip * Cp * SST}}} It means that you consider that liquid precipitation temperature is zero and you calculate the energy given to the ocean by changing the temperature from zero to SST? Am I wrong? 25 ''O Marti''. The temperature is not 0. But NEMO doesn't know at which temperature the precips are leaving the ATM realm to enter the OCE realm, and should make a guess.24 >''A Voldoire'' : Concerning {{{Qrain = lprecip * Cp * SST}}} It means that you consider that liquid precipitation temperature is zero and you calculate the energy given to the ocean by changing the temperature from zero to SST? Am I wrong?[[BR]] 25 >>''O Marti''. The temperature is not 0. But NEMO doesn't know at which temperature the precips are leaving the ATM realm to enter the OCE realm, and should make a guess. 26 26 27 27 28 My understanding is that **in order to be fully conservative, the atmosphere should provide those fluxes**, or am I completely wrong here? 29 O Marti: OK with that. When its rains, some matter is leaving the ATM realm, and an energy is associated with it and given to the OCE realm.28 My understanding is that **in order to be fully conservative, the atmosphere should provide those fluxes**, or am I completely wrong here?[[BR]] 29 > ''O Marti'' : OK with that. When its rains, some matter is leaving the ATM realm, and an energy is associated with it and given to the OCE realm. 30 30 31 31 == What is the solution? == … … 35 35 NEMO needs to know 36 36 and we will have to trick the calculation of snow temperature in LIM3 since it is recalculated from Qsnow (see nota bene). You can see that as NEMO business but it is important you know it has consequences on sea ice thermodynamics.[[BR]] 37 ''O Marti''Not exactly. The flux from atmosphere is not 0. But atmosphere doesn't need to compute it. You could diagnose the actual flux by computing the total ATM enthalpy before and after the rains leaves ATM.37 >''O Marti'': Not exactly. The flux from atmosphere is not 0. But atmosphere doesn't need to compute it. You could diagnose the actual flux by computing the total ATM enthalpy before and after the rains leaves ATM. 38 38 39 39 2) The atmosphere (you, from your atmospheric models) provides non-zero fluxes and then it is better if NEMO knows how Qsnow is calculated in the atmosphere, which Cp, temperature and Lfus is used (see why below).