Tropopause-following analysis of water vapour and ΔD for the monsoon systems and the tropics

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1 Tropopause-following analysis of water vapour and ΔD for the monsoon systems and the tropics Gabriele Stiller, Norbert Glatthor, Stefan Lossow, and the MIPAS team at KIT INSTITUTE OF METEOROLOGY AND CLIMATE RESEARCH, ATMOSPHERIC TRACE GASES AND REMOTE SENSING KIT The Research University in the Helmholtz Association

2 Motivation / open questions How is water vapour transported into the stratosphere? In particular: What role plays overshooting of convection? Are there systematic differences in relevance or frequency for monsoon systems and tropics, respectively? Tropopause altitude varies considerably, on altitude, pressure and potential temperature levels Therefore: analysis directly on tropopause surfaces Data base: MIPAS observations of tem- perature, water vapour and HDO for 2002 to Pan et al.,

3 Motivation / open questions How is water vapour transported into the stratosphere? In particular: What role plays overshooting of convection? Are there systematic differences in relevance or frequency for monsoon systems and tropics, respectively? Tropopause altitude varies considerably, on altitude, pressure and potential temperature levels Therefore: analysis directly on tropopause surfaces Data base: MIPAS observations of tem- perature, water vapour and HDO for 2002 to Pan et al.,

4 Processes leading to depletion and enrichment of heavy water (ΔD) 4

5 H2O, HDO and ΔD at 16 km altitude, JA H2O NAM AMA HDO S-TRO km 5

6 LR Tropopause altitudes from MIPAS AMA NAM S-TRO Tp-height km km 6 20

7 TP temperatures AMA NAM S-TRO Temp at Tp+0 km Temp at Tp+0 km K K 7 20

8 General behavior of TP Altitude: S-TRO: TP highest during SH Summer (16-17 km), lowest around July (< 16 km) AMA: highest TP on absolute scale, km; highest and the most North around July NAM: lower than AMA (~ km), phase and extension as AMA Temperature: S-TRO: T lowest during SH summer (<190 K), highest around July (~ 200K); è lowest WV above TP in SH summer; lowest WV absolute AMA: coldest and furthest North around July, T ~ 195 K; strong temperature contrast and meridional gradient between monsoon and extra-tropics; è low WV during monsoon season, but higher than tropics NAM: less cold than AMA (~ K), less strong meridional gradient; è highest WV of all three regions expected 8

9 9 H2O for AMA, NAM and S-TROP at TP AMA NAM S-TRO S-TROP H2O, Tp+0 km H2O, Tp+0 km H2O, Tp+0 km ppmv ppmv ppmv

10 @ 16 km TP-2km

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14 Pattern of low water vapor on TP surface seems to be linked to West Pacific low CPT region and not to the monsoon region 14

16 Low water vapour comes along with reduced D depletion, in particular over Bay of Bengal and over the Caribbean 16

45 35 25 17 AMA, H2O, delta D, TP-2, TP, TP +2 45 35 25 45 35 25 H2O, Tp+2 km H2O, Tp+0 km H2O, Tp-2 km 20 20 ppmv 8 6 4 2 0 5 0 ppmv 5 0 45 35 25 ppmv

17 AMA, H2O, delta D, TP-2, TP, TP H2O, Tp+2 km H2O, Tp+0 km H2O, Tp-2 km ppmv ppmv ppmv delta D, Tp+2 km delta D, Tp+0 km delta D, Tp-2 km per mil per m per mil

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19 Summary so far q Low water vapor just below and at monsoon tropopause NAM AMA q Pattern of low water vapor on TP surface seems to be linked to West Pacific low CPT region and not to the monsoon region q Low water vapour comes along with reduced D depletion, in particular over Bay of Bengal and over the Caribbean q ΔD enhancements over Bay of Bengal and Caribbean seem not to travel further North in the central monsoon areas q ΔD enhancements over Bay of Bengal and Caribbean seem to be unique features; no similar features exist in the SH during DJF => monsoon related S-TRO q Compare to convection areas over land: 19

20 Seasonal averages over selected regions 4 ASM, JJA, -45N, -130E NAM, JJA, -40N, -160W south. hem., JJA, -30S south Amer., DJF, 22.5S-N, 30-80W 4 ASM, JJA, -45N, -130E NAM, JJA, -40N, -160W south. hem., JJA, -30S south Amer., DJF, 22.5S-N, 30-80W 1 ASM, JJA, -45N, -130E NAM, JJA, -40N, -160W south. hem., JJA, -30S south. Amer., DJF, 22.5S-N, 30-80W Africa, DJF, 22.5S-N, W-40E IND+PAC, DJF, 20S-N, 0E-160W Altitude wrt Tp / km Africa, DJF, 22.5S-N, W-40E IND+PAC, DJF, 20S-N, 0E-160W Altitude wrt Tp / km Africa, DJF, 22.5S-N, W-40E IND+PAC, DJF, 20S-N, 0E-160W H2O / ppmv delta D / per mil 1 0 H2O / ppmv delta D / per mil 20

21 Seasonal averages over selected regions 4 ASM, JJA, -45N, -130E NAM, JJA, -40N, -160W south. hem., JJA, -30S south Amer., DJF, 22.5S-N, 30-80W 4 ASM, JJA, -45N, -130E NAM, JJA, -40N, -160W south. hem., JJA, -30S south Amer., DJF, 22.5S-N, 30-80W 1 ASM, JJA, -45N, -130E NAM, JJA, -40N, -160W south. hem., JJA, -30S south. Amer., DJF, 22.5S-N, 30-80W Africa, DJF, 22.5S-N, W-40E IND+PAC, DJF, 20S-N, 0E-160W Altitude wrt Tp / km Africa, DJF, 22.5S-N, W-40E IND+PAC, DJF, 20S-N, 0E-160W Altitude wrt Tp / km Africa, DJF, 22.5S-N, W-40E IND+PAC, DJF, 20S-N, 0E-160W H2O / ppmv delta D / per mil 1 0 H2O / ppmv delta D / per mil 21

22 Seasonal averages over selected regions 4 ASM, JJA, -45N, -130E NAM, JJA, -40N, -160W south. hem., JJA, -30S south Amer., DJF, 22.5S-N, 30-80W 4 ASM, JJA, -45N, -130E NAM, JJA, -40N, -160W south. hem., JJA, -30S south Amer., DJF, 22.5S-N, 30-80W 1 ASM, JJA, -45N, -130E NAM, JJA, -40N, -160W south. hem., JJA, -30S south. Amer., DJF, 22.5S-N, 30-80W Africa, DJF, 22.5S-N, W-40E IND+PAC, DJF, 20S-N, 0E-160W Altitude wrt Tp / km Africa, DJF, 22.5S-N, W-40E IND+PAC, DJF, 20S-N, 0E-160W Altitude wrt Tp / km Africa, DJF, 22.5S-N, W-40E Randel et al., IND+PAC, DJF, 20S-N, 0E-160W H2O / ppmv delta D / per mil 1 0 H2O / ppmv delta D / per mil 22

23 Preliminary conclusions and further work In contrast to analyses on pressure/altitude/t pot levels the tropopause-following analysis demonstrates that water vapor (WV) minima are located below and at the monsoon tropopauses Above the tropopause WV is slightly (~ 0.5 ppmv) increased above the monsoon systems, compared to the rest of the tropics The Asian monsoon WV minimum is directly connected to that over the West Pacific/maritime continent ΔD helps to understand the phase transition processes during water WV uplift into the stratosphere The monsoon regions have about the same ΔD depletion as other convective regions over land, but are less depleted than the SH inner tropics, and H2O is higher Both findings hint towards uplift and deposition of ice in the TP region (± 2km) to play a more dominating role than in the SH inner tropics Convective processes over the Bay of Bengal and the Caribbean produce clearly enhanced ΔD values hinting towards strong ice lofting processes Future work: refine analysis using also radio occultation temperature data, studying the intra-seasonal variation, and resolving this mystery: 23

24 Preliminary conclusions and further work In contrast to analyses on pressure/altitude/t pot levels the tropopause-following analysis demonstrates that water vapor (WV) minima are located below and at the monsoon tropopauses Above the tropopause WV is slightly (~ 0.5 ppmv) increased above the monsoon systems, compared to the rest of the tropics The Asian monsoon WV minimum is directly connected to that south. over Amer., DJF, the 22.5S-N, West 30-80W Africa, DJF, 22.5S-N, W-40E Pacific/maritime continent IND+PAC, DJF, 20S-N, 0E-160W ΔD helps to understand the phase transition processes during water WV uplift into the stratosphere The monsoon regions have about the same ΔD depletion as other convective regions over land, but are less depleted than the SH inner tropics, and H2O is higher Both findings hint towards uplift and deposition of ice in the TP region (± 2km) to play a more dominating role than in the SH inner tropics Convective processes over the Bay of Bengal and the Caribbean produce clearly enhanced ΔD values hinting towards strong ice lofting processes Future work: refine analysis using also radio occultation temperature data, studying the intra-seasonal variation, and resolving this mystery: delta D / per mil H2O / ppmv ASM, JJA, -45N, -130E NAM, JJA, -40N, -160W south. hem., JJA, -30S 24

25 Preliminary conclusions and further work In contrast to analyses on pressure/altitude/t pot levels the tropopause-following analysis demonstrates that water vapor (WV) minima are located below and at the monsoon tropopauses Above the tropopause WV is slightly (~ 0.5 ppmv) increased above the monsoon systems, compared to the rest of the tropics The Asian monsoon WV minimum is directly connected to that south. over Amer., DJF, the 22.5S-N, West 30-80W Africa, DJF, 22.5S-N, W-40E Pacific/maritime continent IND+PAC, DJF, 20S-N, 0E-160W ΔD helps to understand the phase transition processes during water WV uplift into the stratosphere The monsoon regions have about the same ΔD depletion as other convective regions over land, but are less depleted than the SH inner tropics, and H2O is higher Both findings hint towards uplift and deposition of ice in the TP region (± 2km) to play a more dominating role than in the SH inner tropics Convective processes over the Bay of Bengal and the Caribbean produce clearly enhanced ΔD values hinting towards strong ice lofting processes Future work: refine analysis using also radio occultation temperature data, studying the intra-seasonal variation, and resolving this mystery: delta D / per mil H2O / ppmv ASM, JJA, -45N, -130E NAM, JJA, -40N, -160W south. hem., JJA, -30S 25 Thank you!

Institute of Meteorology and Climate Research (IMK-ASF)

Institute of Meteorology and Climate Research (IMK-ASF) MIPAS observations of the Asian monsoon anticyclone: Focus on water vapor, tracers, and pollutants Gabriele Stiller, Norbert Glatthor, Michael Höpfner, Stefan Lossow, Andreas Wiegele, and Thomas von Clarmann