Presentation on theme: "Director of Center for Climate Change and Air Quality – BMKG"— Presentation transcript:
1Director of Center for Climate Change and Air Quality – BMKG Factors Influencing the Response of the Maritime Continent Climate to ENSODr. Edvin AldrianDirector of Center for Climate Change and Air Quality – BMKGBMKGPresented in XV WMO RA V Bali 30 April – 6 Mei 2010
2Outline of Presentation BMKGThe theory of El NinoPredictability of the maritime continentEl Nino dan climate of the maritime continentENSO impact episodeThe role of local sea surface currentEl Nino and Indian Ocean DipoleImpact of El Nino on the Climate systemEl Nino and global warmingPositive and negative impact of El Nino
3Theory: What is ENSOBMKGENSO is the abbreviation of El Niño Southern OscillationThe term El Nino means ‘Christ Child’ and was first used by Peruvian fishermen in the late 1800’s to describe the warm current appearing off the western coast of Peru around Christmas time.Southern oscillation refers to a seesaw shift in surface air pressure at Darwin, Australia and the South Pacific Island of Tahiti. When the pressure is high at Darwin it is low at Tahiti and vice versa. El Nino, and its sister event – La Nina – are the extreme phases of the southern oscillation, with El Nino referring to a warming of the eastern tropical Pacific, and La Nina a cooling.
4Theory: What is ENSOBMKGThe El Nino is indicated by the movement of warm water mass under the surface of ocean from the warm pool region to the central equatorial PacificWhat is the warmpool region? Is the most warmest equatorial region located in the north of the Papua island and formed after the accumulation of flowing surface warm water in the Pacific Ocean.Why the surface water in the Pacific flows?Due to the earth rotationPart of the Great Ocean Conveyor BeltThe world ventilation system in the oceanWhere the water mass in the warmpool ends? The accumulation of that water mass will from geostropically to the Indian Ocean as the Indonesian Throughflow
5Theory: Why is ENSO Predictable? BMKG“… the time averages (monthly and seasonal means) for the tropics have more predictability. This is because they are largely determined by fluctuations of the seasonally varying boundary conditions of sea surface temperature and soil moisture. Under favorable conditions, they can contribute to the predictability of middle latitudes also.” Shukla, 1981Atmospheric weather is IN PRINCIPLE not predictable more than 2 weeks or so;Over the tropical oceans, the STATISTICS of atmospheric weather depends on the sea surface temperature (e.g. Rains over warm water);Sea surface temperature CAN be predicted by a coupled atmosphere-ocean model if the internal state of the upper tropical ocean in known;Skill is likely to be much less in mid-latitudes because the SST determines the statistics in the presence or much variability.
6Climatology of regional rainfall BMKGMainly monsoonalThree distinct rainfall climate regionsAldrian and Susanto, 2003, Intl J Climatol.monsoonalSemi-monsoonalAnti-monsoonal
7Interannual variability in Region A BMKGAldrian et al, 2007, Theo. Appl. Climatol.
8Interannual variability in Region B BMKGAldrian et al, 2007, Theo. Appl. Climatol.
9Interannual variability in Region C BMKGAldrian et al, 2007, Theo. Appl. Climatol.
10Wide range SST responses to rainfall in region A BMKGWeak response in spring, no ENSO influenceStrong two dipoles in SON (Walker cell)Role of SPCZ in SONAldrian and Susanto, 2003, Intl J Climatol.
11Wide range SST responses to rainfall in region B BMKGWeak response in all season, especially in springno ENSO influence and walker cellAldrian and Susanto, 2003, Intl J Climatol.
12Wide range SST responses to rainfall in region C BMKGWeak response in springStrong two dipoles in SON (Walker cell) like region ARole of SPCZ in SON like in region AAldrian and Susanto, 2003, Intl J Climatol.
13Skills of monthly rainfall variability BMKGResponse to ENSONegative responses to NINO3 SSTSignificant in MJJAS(similar to Hendon, 2003)Variability in comparison to observations(correlation values)Strong responses in Region A and CSpring is the least responsive seasonECHAM4 responds well to ENSOAldrian et al, 2007, Theo. Appl. Climatol.
14The Indonesian Throughflow BMKGThe Indonesian Throughflow
15ENSO and ocean: Climate BMKGNormal conditionEl Nino conditionLa Nina condition
16Decadal signals of the maritime continent (Aldrian and Djamil 2008)After monsoon and ENSO signalsBMKG
17El Niño impact episodeBMKGEnsemble El Niño events during against climatology
18La Niña impact episodeBMKGEnsemble La Niña events during against climatology
19ENSO episodes between rainfall and NINO3 SST BMKGimpact starts in AprilNo impacts on the peak of rainfall season in DJFThe ocean mechanism prevents the impact during the wet seasonEl Nino is in-phase to the dry season, thus worsen the caseLa Nina has no impact in the peak of the dry season MJJ because they are out-of-phase
20Monsoonal climatology of the Maritime Continent BMKG
21Surface sea current (Wyrtki 1962) BMKGJuneDecember
22Role of ocean circulation in limiting the ENSO impact BMKGAldrian, Disertation thesis, 2003
23FACTORS CONTROLLING RAINFALL IN INDONESIA El Nino and other climate charactersFACTORS CONTROLLING RAINFALL IN INDONESIAA S I A1Ags -SepOkt - NovEL NINO / LA NINADIPOLE MODE POSITIFVE/ DIPOLE MODE NEGATIVE42A F R I C A3INDONESIAN SST14MONSOONAL WINDS31963197219821997EL NINO (ºC)SEP 091.38/ ModOKT 091.95/ ModNOV 092.07/ KuatDES 091.94/ Mod2A S I AAgs -SepOkt - NovDIPOLE MODE (ºC)SEP 09(+) 0.38/ NetralOKT 09(+) 0.40/ NetralNOV 09(+) 0.32/ NetralDES 09(+) 0.22/ Netral4A F R I C A13ARAHANGIN MUSIMAGS – SEP TIMURANOKT– NOV BARATAN2
24Indian Ocean Dipole El Nino and other climate characters BMKGThe Indian Ocean Dipole (IOD) is a coupled ocean-atmosphere phenomenon in the Indian Ocean. It is normally characterized by anomalous cooling of SST in the south eastern equatorial Indian Ocean and anomalous warming of SST in the western equatorial Indian Ocean. Associated with these changes the normal convection situated over the eastern Indian Ocean warm pool shifts to the west and brings heavy rainfall over the east Africa and severe droughts/forest fires over the Indonesian region.
25Partial correlation between Indian Ocean and ENSO in the maritime continent BMKGPurwaningtyas and Aldrian 2008Western pole - rainfallEastern pole - rainfall
26Delineation of ENSO and Indian Ocean Dipole impacts BMKGPurwaningtyas and Aldrian 2008
27EL NIÑO DAN DIPOLE MODE 1957 – 2007 UpdateEL NIÑO DAN DIPOLE MODE 1957 – 2007EL ÑINOPERIODAnomaliSuhu Muka Laut (0 C)Central Pasifik (El Nino)Indonesian waterIndian Ocean (Dipole Mode)JAS NDJ 1951/52+ 0.8-0.38MAM 1957 – MJJ 1958+ 1.7-0.40JJA 1963 – DJF 1963/64+ 1.0-0.51+ 1.5MJJ 1965 – MAM 1966+ 1.6-0.46+ 0.13OND 1968 – MJJ 1969-0.16- 0.12ASO 1969 – DJF 1969/70-0.30+ 0.58AMJ 1972 – FMA 1973+ 2.1-0.45 (cool)(strg)ASO 1976 – JFM 1977-0.45+ 0.92ASO DJF 1977/78-0.60+ 0.5AMJ 1982 – MJJ 1983+ 2.3-0.60 (cool)(strg)JAS 1986 – JFM 1988+ 1.6-0.05+ 1.88AMJ 1991 – JJA 1992+ 1.8-0.23+ 1.56AMJ 1994 – FMA 1995+ 1.3-0.52+ 2.73AMJ 1997 – AMJ 1998+ 2.7 – 3.2-0.29 (cool)(strg)AMJ 2002 – FMA 2003+ 1.50.17 (neutral)+ 0.96MJJ 2004 – JFM 2005+ 0.9-0.06- 0.19JAS DJF 2006/07+ 1.1-0.25 (cool)+ 1.59Agustus 200919 Sept+0.82+0.650.6(warm)+0.63-0.3 (neutral)-0.33Sumber : NOAALevel EN & DMEN Kuat > 2.0 0CEN Moderate 1.0 – 2.0 0CEN Lemah 0.5 – 1.0 0CTahun 1972; 1982; 1997:Pada tahun yang sama, 2 fenomena, El Nino & Dipole Mode terjadi bersama-sama curah hujan di wilayah Indonesia berkurang banyak karena didorong dari:Pantai barat Sumatera ke Afrika TimurWilayah perairan Indonesia ke Pasifik TengahPerhatikan: Kekuatan El Nino dan Suhu perairan1997: EN KuatSuhu perairan Indonesia ; dingin2009; EN Lemah – ModerateSuhu Perariran Indonesia; hangat27
28Detecting El Nino from Indonesian seas BMKGData from modeling Indonesian seas from the entrance and exit channel of the throughflow could be used as the precursor of the incoming El Nino up to 5 month in advance with high confidence levelDuring El Nino the climate predictability of the region is high
29During La Nina (El Nino) the termocline layers will transport more (less) water mass due to ENSO modulations (Meyers, 1996). Large water mass transport is usually associated with a higher density or higher salinity water, thus whenever this layers is modulated, the water composition and density will change accordingly.BMKG
30El Nino and Indonesian climate BMKGDuring El Nino, the Indonesian water will be cooler high surface pressure in the MC, winds from Australia will be diverted to the southtern coast of MC create Ekman pumping and upwelling there good for fishery there and western coast of Sumatera. Ironically cool SST will induce drought especially in the western part of MC or the eastern dipole of the Indian Ocean. Hence, most of El Nino will be associatively related to the positive Dipole Mode. Moreover El Nino usually shutdown the MJO potency in that year.
31Climate Feedback and forest fire BMKGAldrian 2007annual SSTAug-Dec SSTKalimantanSumatera0.940.830.950.930.900.800.770.750.840.850.871
32ENSO & FisheryBMKGAccording to Hendiarti et al (2005) fishery catch in seas around Java is highly seasonal. Catch decrease during El Nino in Sunda Strait, but increase in east Java.
33Impact of climate change and ENSO over the deep sea BMKGThe global warming will increase surface temperature and its subsurface layer. Changes in temperature will largely occur in the mixing and thermocline layers. Subsequently marine acosystem will change due to comfort zone of living by ocean species.
34Impact of climate change and ENSO over the deep sea BMKGBecause of global warming or strong La Nina episodes and rising of surface temperature, the ocean species will swim deeper to find the same comfort zone as before global warming happens. As a result the fish catchment must go deeper. The reverse pattern is true during El Nino event when the fish catchment increase because fish swim in shallower layers.
35Impact of global warming on the evolution of El Nino (higher frequency) (present decade and last 3 decade)BMKG
36Impact of global warming on the evolution of El Nino (higher intensity) BMKG
37Why El Nino intensifier due to global warming BMKGThe Warm pool is formed due to global thermohaline circulation (the great ocean conveyor belt) and brings surface sea water from north, south and equatorial Pacific. Those surface water is notable warm because direct solar radiation. The warm pool is the main gate of water flow from the Pacific to the Indian OceanEl Nino occurs during the movement of subsurface warm pool from north of Papua to central Pacific because the subsurface temperature gradient over the warm pool and central Pacific exceed the critical threshold. By classic fluid dynamics this condition will allow propagation of water masses, thus creating El NinoGlobal warming will make faster warmer warm poolWith faster and warmer warm pool, the potency to exceed the threshold level will be faster and allowing propagation of water mass El Nino
38Competing feature of ENSO and global warming in the region BMKGAs the earth surface temperature warmer, the evaporation rate over the tropics will increase faster and higher water cycleThere is a tendency of wetter dry season over the maritime continent case 2009Aldrian and Susanto, 2003, Intl J Climatol.
40Negative impacts of El Nino BMKGLong drought and strong potency of forest fireSurface water deficit and water deficit in the reservoirs, lake, dams and riversLong drought means harvest failure especially in the paddy fieldMajor El Nino issues: rice import, water pump, irrigation and water resources
41Positive impact of El Nino BMKGFishery sector will be booming as the fish swim nearer to the surfaceSalt industry will be booming due to longer solar radiationSeaweed industry will be booming with cooler surface sea water
42Positive impact of El Nino BMKGTransport sector no weather extremeSeveral agriculture commodities will gain better harvest such as onion, tabacco, teakwood, corn etc.Construction sectors will gain better such as building development and the cement industryTourism sector will gain benefit due to longer solar radiation
43CONCLUSIONSBMKGThe maritime continent has high seasonal predictability from tropical and maritime charactersENSO is the second largest influences of regional climate phenomena, whose influences are confined during the dry season due to monsoonal sea surface pattern. event and impact are differentIndian Ocean dipole, monsoon and global warming are confounding factors affecting the impact of ENSO in the regionGlobal warming has intensifier the frequency and intensity of ENSO but on the other hand warmer and wetter the maritime sea and climate