Special Topics in Atmospheric and Oceanic Sciences
Special Topics in Atmospheric and Oceanic Sciences ATOC 7500
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Date Created: 10/30/15
Asian 8qu And A r I f Jason Englis i ATOC 7500 May 4 200 Aerosols amp Climate Global cooling effect but spatially variable forcings may affect global circulation eg regional warming or cooling Why are aerosols important Direct Direct scattering albedo albedol effect E light Addressed in AR4 1st indirect albedo Indirect effect 2nd indirect cloud lifetime T Semidirect cloud evapT Glaciation ice nuclei precipT Thermodynamic smaller colder drops Sfc energy budget heat ux precip l IPCC AR4 2007 ma quota anthropogenic RF Terms RF values w m 2 x 1 c I 166l1AQIo183 Gum Higw Lon Viived 39 greenhouseggases N20 1 045 0 43 m 0551 memns 01 139 4 3v 0 8 Global ng39l 1 Cormnemnl Med 2 Ozone Slrafosphenc TmPosphznc 1 Ms 025 0 Ms W gm 0 SImmspheric water a g Vapour from CH 1 007 0 02 In 012 Global Law E Land use I o2 04 In 00 Local m Med Surface albedo Su sm DJ 0010 021 comrental IW r r Communal Med Tom I 5mm Total aerosol M 0 9 quot 0quot mammal Law A l I I L Sam 1 We amp 1 417 15 m 413 email Lmt Ind II eC t effect I Unearwnna s 001 o no to o 03 Connnemal Law 5 l E Solar irradiance 012 006 m 030 elm Law 16 D 5 lo 24 1 o 1 Radiative Forcing W m39a VUV lSM Ll What are aerosols Tiny solidliquid particles mixture of key types below plus water If Kohler cune Type Min Size Annual load Anthro Key Source RF Wm39z I Sulfate 001 um 110 T9 75 fossil fuels o4o I Black Carbon 001 um 22 T9 100 biomass 020 Organic Carbon 001 um 130 T9 80 biomass 010 Nitrate 001 um 50 T9 50 fossil fuels 010 Dust 1 um 2000 T9 40 deserts 010 Sea Salt 1 um 3000 T9 0 oceans 0 Combined 050 is overcome 1 um coagulation paouanuulueulnl l Nucleation mode CCN unactivated haze Accumulation mode GCCN cloud drops Drizzle mode drizzle Sulfur Cycle n M sm Em 3 growthcomposition 4 3D distribution transport 2 sulfate formation m slum m IhIwhmn IllIf mmm El l i G r 39 Simian A sultan in all rm aimsd m 391 r 39 mm 7 1 sulfur emissions 39 httpjanuccnauedudoetqpcoursesenv440env4402 Pr 39 I ecturesec37ec37htm t a 1 Sulfur emissions transportation combustion my industrial 3 gtquot shlggng volcanoes biomass burning S aquot a 0quot o I sulfur dioxide I Anthropogenic 76 Natural 24 Marine plankton HBCSCH3 biomas2stytl33urning dimethysufide terrestrial Spiro et al JGR 1992 and EDGAR database 2000 2 sulfate Formation Oxidation of 802 Primary lam 011 so OHIM HSDgM Gas phase T H0502 39 quot 3303 02 gt 303H02 fast Hoso2 SUg HgO h gt H2304M fast I 302m Hr sagH20 j d r phase mm H HsogH Hz ac mm H202 1 503 2H H20 39 eg39r 7 m Mass Extinction Efficiency m 261 Single Scat Albedo 9 Effect of size on RF 77m I llllllll I llllllll dry n 15 00051 wet n 137 0001139 lll lllll III I a 2 4 l l 6 B 2 6 1 Diameter pm 02 to 2 um diameters scatter the most light per unit mass Hydration dotted line has higher SSA but less per unit aerosol mass IPCC 2001 How Models deal with Sulfates kit I 2 Formation 395 lllll sit ll o llij Reactions 39 3 Growth Composition 4 Transport immirlm Dynamics 5 Removal aDescribed in Barth et al JGR 2000 bCurrent WACCM uses MOZARTS CAM wsulfur turned off CMOZART4 is under development at NCAR Loisa Emmons CAMCHEM is under development at NCAR Francis Vitt Question to answer If regional aerosol RF is high enough can it alter global circulation causing climate change in other regions Global aerosol RF 05 Wm2 mines 02 ASia aerOSOI I m 10 to 50 Wm2 includes natural 0 JFMAMJJASDND Month Sulfur Emissions Dataset Source GEIA Emissions Dataset 1990 Seasonal projections every 15 years 19902095 1 x 1 Flux resolution kg m2 s CAM translates the data by converting emissions data grid to simulation data grid 4x5 Keeping emissions constant until next 15year period SOX field 4 dimension array 1 Date field32 Seasonal 4 emissionsyear x 8 unique years 2 Leves2 0 m 100m 3 Latitude46 4 degree increments 180 degrees total 4 Longitude72 5 degree increments 360 degrees total Scenario Designs Base Case 4 x 5 resolution 002 1 increaseyr Sulfur Prognostic Active 20052028 compared 14yr averages 20152028 Zero Asian sulfur Emissions Set emissions to zero for 8 52 latitude 60 135 long ude 10x Asian sulfur Emissions Multiplied each grid box by 10 for 8 52 latitude 60 135 long ude Anthropogenic Sulfur Emissions by Scenario Annual Average 20052025 Scenario Total Emissions Asian Emissions 8052O latitude 600135O longitude CAM Default 0 T9 0 T9 0 of total Base Case 73 T9 29 T9 40 of total Zero Asian 44 T9 0 T9 0 of total 10x Asian 335 T9 290 T9 87 of total ARGTA ILQE PEAN i395 gamma OCEAN SOxemissions4x5nonconc050306nc SOx emissions Standard GEIA 2005 Emissions lat degreesnorth o 40 40 200 Ion degreeseast Sul Jr emissions C kgrays u 4 054711 8054111 1 2541147 sex or in39 1m 0 m 22nn5m151 SOxemissions4x5nonconc050306nc NoAsia Zero Emissions 2005 Emissions lat degreesnorth 0 40 40 0 100 200 300 Ion degreeseast Sulfur emissions i i i i i 2 7 4 05011 5 05011 1 2942147 Kgm s WWW SOxemissions4x5nonconc050306nc S x emissions 4a is 5 r I 3 E a U a E E 40 0 200 Ion degreesieast Su furemwsswons kgmZs a 0147 3 De 010 4 0542147 1 0547147 2 Us saxnw war we cu2nn5m15 SO4 load base case 20052028 504 kgkg 10 1015 4593 HF u gmnm average 200000 400000 500000 000000 Days since 0mm 0 0000 G oba Atmosphe c 804 oad 5 rougmy constant from 200572025 OSC HZUOH rmrrors Season ermss ons rate Global Surface T base case 2005 2028 TS K g obc average 253 m E 0 287 A m 000 200000 400000 500000 000000 Days since 0mm 0 0000 z w a GlobalsurfaceT a N and S Hemisphere summer Global Avg Surface Temp Change Base Case Zero emissions simulation TS K global average i i i l mm 2000 um mum 500000 Days since man i 0000 01 deg 0 increase in global avg sfc Temperature Global Avg Surface Temp Change Base Case 10x simulation TS K global average l sumo l l mm mm mm mum Days since man i 0000 03 deg C decrease in global avg sfc temp why such a small difference This is 300 Tg sulfur Global Avg Convective Precip Change Base Case Zero emissions simulation PRECC ms global average moquot 2xwquot 2xmquot i mum 500000 Du 5 since Uldan l 0000 0 change in global average Precip why Poor atmosphereocean coupling Decrease in Indian monsoon l l mm mm mm Avg 802 change 20152028 Zero Emissions Scenario 502 kgkg 25Jcm 7 moo cu 10054593 hPu 5 a 435 790 7 L MmmDmmUnmInmnMaph gnuWm m Avg SO4 change 20152028 Zero Emissions Scenario 504 kgkg QSJcm 7 900 cu 10054593 hPu a an r u 7135 ego w M Q g r 331 BWMg o as q a so 430 435 790 Mummmmmmmr Wm M Ophcar Depth Decreases by 3 5r forme y heavy ermssrons regrons 178 Transport 5 50 decreases Ophcar depth across Pacmc Oceah Avg OD change 20152028 Zero Emissions Scenario AERDDV Nuns ZEJun 7 1200 5 so 135 r u 7135 79 745 u 250 f 45 as r u 435 e u 745 mumm omrcar Depm Decreases by 3 5 rn rorrnerry heavy ernrssrons regrons mm m Zonar Transport arso decreases omrcar depm across Pacrrrc Ocean Tms seerns too mgr by a factor or 10 averagmg procrern Avg Surface Temp Change 20152028 Zero Emissions Scenario T change K Zero scenano 7 base case 5 an 135 mm 7135 79 D L w w i g 45 ED 135 mm 7135 790 745 MM Warrmng Where aeroso s are removed quotmm me No change wer oceans Warrmng m s bena N A Coohng m Greemand BrazH Avg Convective Precip 20152028 Convectwe WmmDulaMmwmwwmnAmnmhuuwDqu H mm mm ma Avg Convective Precip Change 20152028 Zero Emissions Scenario Precrp cnange mS Zero scenano 7 base case ram 7135 790 45 EU as mu 435 r430 745 mmwpmr Mom ncrease m convectwe oreoro overAswa rnore RE rnore vemca veroorty ncrease m 10 deg N decrease at the Equator except nearAswa Ewdence of a nonnwaro snrn orAsran Monsoon TCZ Avg Convective Precip Change 20152028 Zero Emissions Scenario Frac Precip increase Zero scenan ase case base case M idiiiii r iiii m di i i wwwz 10 60 decrease over parts of Middie East Evidence ofa iTCZ Shift Avg Stable Precip 20152028 Zero Emissions Scenario Stable precip mls I mm 7135 WmmmmewAmmmmmw H mm mow mm Avg Stable Precip Change 20152028 Zero Emissions Scenario Precip change ms Zero scenario base case I u 7135 79 745 6 an 135 is manmuumDmph swim mm mm m n k u L M ha Evidence ofa ITCZ shi to the North Avg Stable Precip Change 20152028 Zero Emissions Scenario Frac Precip increase Zero scenan ase case base case I No change in Stabie precip overASia no giobai circuiation changes in this region WW1 we 10 60 decrease over parts of Middie East Evidence ofa iTCZ Shift Zonal Circulation H Summmca JEK Stream Zonal V nds Zero Emissions 20152028 Zero Emissions Scenario Zonai Wnd Speed change ms 5 90 35 U 5 MmMmmwwmemwmm mm ms mm was Change in Horizontal Winds 20152028 Zero Emissions Scenario Zonai vwm Speed change ms Zero Scenario 7 base case so 45 Shi in ITczf hbtropicaI Jet Polar Jets Change in Horizontal V nds 20152028 Zero Emissions Scenario Meridionai Wind Speed cnange mS 10x Scenario 7 base case is an 135 ism 435 79 745 UlmuiiInDmph swim iiim mm m Sni in iTCZ Avg OD Change 20152028 WWWW WWWMWWWWm mm mm m 10x the optwca depth ofbase case Optwca depth contmues to be Suapwcwousw mgh averagmg amacm Avg Surface Temp Change 20152028 10X Emissions Scenario T cnange K 10x scenan ase case m Opposne te econnectwons as Zero Emwsswons mum Coohng Wheremx eroso s added Coohng m s bena N A Warmmg m Greemand No cnange over oceans Avg Convective Precip Change 20152028 10x Emissions Scenario I Precip change ms 10x scenario base case I 65 90 i 5 ism 135 u 745 45 gm was mm 435 rem e45 Opposite leleconneclions as Zero Emissions r r a ue nr 39 39 1 Increase in 10 deg N decrease at the Equaior except near Asia Evidence of a southward shi of Asian Monsoon TCZ Change in Horizontal V nds 20152028 10x Emissions Scenario Zonai vwm Speed change rns 10x Scenario 7 base case 5 45 mmm umin unuIh mm mm Major wind shi in Asia Giant High at 90 longitude I30 Latitude Change in Horizontal V nds 20152028 10x Emissions Scenario Meridionai vwm Speed change rns 10x Scenario 7 base case wwwm umin mutth mm M Major wind shi in Asia Giant High at 90 longitude I30 Latitude Other Studies Kim et al 2006 Dust and BC in Africa Asia excite a planetaryscale teleconnection pattern in sea level pressure temperature and geopotential height spanning North Africa through Eurasia to the North Pacific Gu et al 2006 Aerosol RF causes cooling in China reducing the T gradient to the North reducing tropical convection Lau et al 2006 Increased Asian aerosol loading increases the circulation of a High Pressure over the Tibetan continent Summary Asia sulfur emissions inversely related to Asian surface temp amp precip Global circulation ITCZ subtropical jets polarjets move 100 s of km inducing significant changes to regional precipitation and temp Consistent with other simulations which suggest aerosol induced circulation changes Next Steps Repeat base case with modified start date to quantify model variability Compare ADD to satellites confirm that there was no error in simulation calculations Look into regional temp and precip changes over the past 50 years and compare to simulation results Investigate CAM s oceanatmosphere coupling and improvements to it Quiz What s more reliable for quantifying aerosol RF Observations or Models ANSWER NEITHER Optical depth a 550 nm averaged over the ocean x x obs Nakuima and mgmasm result b5 Nakulma and mgurasm Issu 2 s Mlsmhenko smwe January 0394 esrc cht rammoua ULAO scum emmoun 5 Max Planckl Da housm u 303 Summedsens ysludy 3 76 2 o 002 01 o 39 w u l 70 50 30 1o 10 30 50 7o Latitude PCC 2001 References Title Atmospheric teleconnection over Eurasia induced by aerosol radiative forcing during boreal spring Authors Kim MK Kim MaengKi Lau WKM Lau William K M Chin M Chin Mian Kim KM Kim KyuMyong Sud YC Sud Y C Walker GK Walker Greg K Source JOURNAL OF CLIMATE 19 18 47004718 SEP 2006 Document Type Article Language English Cited References 65 Times Cited 0 Find Related Records Information Abstract The direct effects of aerosols on global and regional climate during boreal spring are investigated based on numerical simulations with the NASA Global Modeling and Assimilation Office finitevolume general circulation model vaCM with Microphyics of Clouds with the RelaxedArakawa Schubert Scheme McRAS using aerosol forcing functions derived from the Goddard Ozone Chemistry Aerosol Radiation and Transport model GOCART The authors find that anomalous atmospheric heat sources induced by absorbing aerosols dust and black carbon excite a planetaryscale teleconnection pattern in sea level pressure temperature and geopotential height spanning North Africa through Eurasia to the North Pacific Surface cooling due to direct effects of aerosols is found in the vicinity and downstream of the aerosol source regions that is South Asia East Asia and northern and western Africa Significant atmospheric heating is found in regions with large loading of dust over northern Africa and the Middle East and black carbon over Southeast Asia Paradoxically the most pronounced feature in aerosolinduced surface temperature is an eastwest dipole anomaly with strong cooling over the Caspian Sea and warming over central and northeastern Asia where aerosol concentrations are low Analyses of circulation anomalies show that the dipole anomaly is a part of an atmospheric teleconnection pattern driven by atmospheric heating anomalies induced by absorbing aerosols in the source regions but the influence was conveyed globally through barotropic energy dispersion and sustained by feedback processes associated with the regional circulations The surface temperature signature associated with the aerosolinduced teleconnection bears striking resemblance to the spatial pattern of observed longterm trend in surface temperature over Eurasia Additionally the boreal spring wave train pattern is similar to that reported by Fukutomi et al associated with the boreal summer precipitation seesaw between eastern and western Siberia The results ofthis study raise the possibility that global aerosol forcing during boreal spring may play an important role in spawning atmospheric teleconnections that affect regional and global climates References Title Climatic effects of different aerosol types in China simulated by the UCLA general circulation model Authors Gu Y Gu Y Liou KN Liou K N Xue Y Xue Y Mechoso CR Mechoso C R Li W Li W Luo Y Luo Y Source JOURNAL OF GEOPHYSICAL RESEARCHATMOSPHERES 111 D15 Art No D15201 AUG 1 2006 Document Type Article Language English Cited References 57 Times Cited 0 Find Related Records Information Abstract The climatic effects of various types of aerosol in China have been investigated by using the atmospheric general circulation model AGCM developed at the University of California Los Angeles UCLA The model includes an efficient and physically based radiation parameterization scheme specifically developed for application to clouds and aerosols Simulation results show that inclusion of a background aerosol optical depth of 02 reduces the global mean net surface solar flux by about 5 W m2 and produces a decrease in precipitation in the tropics as a result of decreased temperature contrast between this area and the middle to high latitudes which suppresses tropical convection These decreases have partially corrected the overestimates in the surface solar flux and precipitation in the UCLA AGCM simulations without the aerosol effect The experiment with increased aerosol optical depths in China shows a noticeable increase in precipitation in the southern part of China in July due to the cooling in the midlatitudes that leads to the strengthening of the Hadley circulation Aerosol types play an important role in the determination ofthe global mean radiation budget and regional climate While sulfates mainly reflect solar radiation and induce negative forcing at the surface black carbon and large dust particles absorb substantial solar radiation and have a positive solar forcing at the top of the atmosphere but reduce the solar radiation reaching the surface Large dust particles also have a significant effect on thermal lR radiation under clear conditions but this effect is largely masked by clouds generated from the model in AGCM simulations Black carbon and large dust particles in China would heat the air column in the middle to high latitudes and tend to move the simulated precipitation inland ie toward the Himalayas The inclusion of black carbon in our simulations has not produced the quotnorth droughtsouth floodingquot precipitation pattern that has frequently occurred in China during the past 50 years References Title Observational relationships between aerosol and Asian monsoon rainfall and circulation Authors Lau KM Lau K M Kim KM Kim K M Source GEOPHYSICAL RESEARCH LETTERS 33 21 Art No L21810 NOV 8 2006 Document Type Article Language English Cited References 21 Times Cited 0 Find Related Records Information Abstract Preliminary observational evidences are presented showing that the Indian subcontinent and surrounding regions are subject to heavy loading ofabsorbing aerosols ie dust and black carbon which possess spatial and temporal variability that are closely linked to those of the Asian monsoon water cycle Consistent with the Elevated Heat Pump hypothesis we nd that increased loading ofabsorbing aerosols over the lndoGangetic Plain in the premonsoon season is associated with a increased heating ofthe upper troposphere with the formation of a warmcore upper level anticyclone over the Tibetan Plateau in April May b an advance ofthe monsoon rainy season in northern India in May and c subsequent increased rainfall over the Indian subcontinent and decreased rainfall over East Asia in JuneJuly References Title Global impacts of aerosols from particular source regions and sectors Authors Koch D Koch Dorothy Bond TC Bond Tami C Streets D Streets David Unger N Unger Nadine van der Werf GR van der Werf Guido R Source JOURNAL OF GEOPHYSICAL RESEARCHATMOSPHERES 112 D2 Art No D02205 JAN 24 2007 Document Type Article Language English Cited References 49 Times Cited 1 Find Related Records Information Abstract 1 We study the impacts of presentday aerosols emitted from particular regions and from particular sectors as predicted by the Goddard Institute for Space Studies GCM We track the distribution and direct radiative forcing of aerosols including sulfate and black and organic carbon emitted from major source regions North America Europe south Asia Southeast Asia South America and Africa We also partition the emissions by sector including industrial power residential transport biomass burning and natural Southeast Asia produces 15 and 10 of the world39s black carbon and sulfate and exports over 2 3 ofthis burden over the Northern Hemisphere About 1 2 of the S02 emitted by Southeast Asia and Europe is not converted to sulfate because of oxidant limitation Although Africa has the largest biomass burning emissions South America generates a larger about 20 ofthe global carbonaceous aerosol burden about 1 2 ofthis burden is exported and dominates the carbonaceous aerosol load in the Southern Hemisphere Calculated direct anthropogenic radiative forcings are 029 006 and 024 W m2 for sulfate organic and black carbon respectively The largest BC radiative forcings are from residential 009 W m2 and transport 006 W m2 sectors making these potential targets to counter global warming However scattering components within these sectors reduce these to 004 and 003 W m2 respectively Most anthropogenic sulfate comes from power and industry sectors and these sectors are responsible for the large negative aerosol forcings over the central Northern Hemisphere KeyWords Plus GENERALCIRCULATION MODEL BLACK CARBON AEROSOL ORGANICCARBON 3DIMENSIONAL MODEL CLIMATE SENSITIVITY GODDARD INSTITUTE LIGHTABSORPTION FUEL COMBUSTION SULFUR CYCLE ART References Title Local and remote impacts of aerosol climate forcing on tropical precipitation Authors Chou C Neelin JD Lohmann U Feichter J Source JOURNAL OF CLIMATE 18 22 46214636 NOV 2005 Document Type Article Language English Cited References 33 Times Cited 2 Find Related Records Information Abstract Mechanisms that determine the direct and indirect effects of aerosols on the tropical climate involve moist dynamical processes and have local and remote impacts on regional tropical precipitation These mechanisms are examined in a climate model of intermediate complexity quasiequilibrium tropical circulation model QTCM forced by prescribed aerosol forcing which is obtained from a general circulation model ECHAM4 The aerosol reflection is the dominant aerosol forcing while the aerosol absorption has complex but much weaker influences on the regional tropical precipitation based on the ECHAM4 aerosol forcing The local effect associated with aerosols contributes negative precipitation anomalies over convective regions by affecting the net energy flux into the atmospheric column This net energy flux is controlled by the radiative forcing at the top of the atmosphere on time scales where surface heat flux is near equilibrium balancing anomalous solar radiation by evaporation longwave radiation and sensible heat Considering the aerosol absorption effect alone the associated precipitation anomalies are slightly negative but small when surface heat fluxes are near equilibrium Two effects found in global warming the uppedante mechanism and the anomalous gross moist stability mechanism occur with opposite sign in the aerosol case Both act as remote effects via the widespread cold tropospheric temperature anomalies induced by the aerosol forcing In the uppedante mechanism in global warming a warm troposphere increases the lowlevel moisture quotantequot required for convection creating spatially varying moisture anomalies that disfavor precipitation on those margins of convective zones where the mean flow imports air from nonconvective regions In the aerosol case here a cool troposphere preferentially decreases moisture in convective regions creating positive precipitation anomalies at inflow margins In the anomalous gross moist stability mechanism for the aerosol case the decrease in moisture in convective regions acts to enhance the gross moist stability so convection and the associated precipitation are reduced The partitioning between the aerosol local and remote effects on regional tropical precipitation differs spatially Over convective regions that have high aerosol concentration such as the South American region the aerosol local effect contributes more negative precipitation anomalies than the anomalous gross moist stability mechanism in the QTCM simulations On the other hand the remote effect is more important over convective regions with small aerosol concentrations such as the western Pacific Maritime Continent Remote effects of midlatitude aerosol forcing have a substantial contribution to tropical anomalies References Authors Ramanathan V Crutzen PJ Lelieveld J Mitra AP Althausen D Anderson J Andreae MO Cantrell W Cass GR Chung CE Clarke AD Coakley JA Collins WD Conant WC Dulac F Heintzenberg J Heymsfield AJ Holben B Howell S Hudson J Jayaraman A Kiehl JT Krishnamurti TN Lubin D McFarquhar G Novakov T Ogren JA Podgorny lA Prather K Priestley K Prospero JM Quinn PK Rajeev K Rasch P Rupert S Sadourny R Satheesh SK Shaw GE Sheridan P Valero FPJ Source JOURNAL OF GEOPHYSICAL RESEARCHATMOSPHERES 106 D22 2837128398 NOV 27 2001 Document Type Article Language English Cited References 87 Times Cited 248 Find Related Records Information Abstract Every year from December to April anthropogenic haze spreads over most ofthe North Indian Ocean and South and Southeast Asia The Indian Ocean Experiment INDOEX documented this lndoAsian haze at scales ranging from individual particles to its contribution to the regional climate forcing This study integrates the multiplatform observations satellites aircraft ships surface stations and balloons with one and fourdimensional models to derive the regional aerosol forcing resulting from the direct the semidirect and the two indirect effects The haze particles consisted of several inorganic and carbonaceous species including absorbing black carbon clusters fly ash and mineral dust The most striking result was the large loading of aerosols over most ofthe South Asian region and the North Indian Ocean The January to March 1999 visible optical depths were about 05 over most of the continent and reached values as large as 02 over the equatorial lndian ocean due to longrange transport The aerosol layer extended as high as 3 km Black carbon contributed about 14 to the fine particle mass and 11 to the visible optical depth The singlescattering albedo estimated by several independent methods was consistently around 09 both inland and over the open ocean Anthropogenic sources contributed as much as 80 10 to the aerosol loading and the optical depth The in situ data which clearly support the existence of the first indirect effect increased aerosol concentration producing more cloud drops with smaller effective radii are used to develop a composite indirect effect scheme The lndoAsian aerosols impact the radiative forcing through a complex set of heating positive forcing and cooling negative forcing processes Clouds and black carbon emerge as the ma or players The dominant factor however is the large negative forcing 20 4 W m2 at the surface and the comparably large atmospheric heating Regionally the absorbing haze decreased the surface solar radiation by an amount comparable to 50 of the total ocean heat flux and nearly doubled the lower tropospheric solar heating We demonstrate with a general circulation model how this additional heating significantly perturbs the tropical rainfall patterns and the hydrological cycle with implications to global climate