Lec1 monsoon

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<ul><li> 1. Monsoon Climate Part1 W4930 Earths oceans and atmosphere 03/24/05Chie Ihara</li></ul> <p> 2. What is monsoon? Where can we see monsoons? Why are monsoons important? What is the physical mechanism ofmonsoon? Examples: Asian monsoon, NorthAmerican monsoon, West Africanmonsoon Can we predict monsoons? 3. What is monsoon?A name for a wind system thatchanges in speed and directionwith season. (derived from an Arabword) 4. Surface Wind: January 5. July 6. Where?Asian monsoonAsian-AustralianAustralian monsoon monsoonNorth AmericanmonsoonAfrican monsoon 7. Cold season: Dry winds blow from land tooceanWarm season: Wet winds blow from ocean tolandtransport moisturelarge rainfall 8. Why are monsoon rainfalls important? water management, disaster mitigation, agriculturalefficiencye.g.) Asian monsoonsAbout 60% of the worlds population depends onmonsoone.g.) Asian monsoons (India)8.2 % economic growth in the yearending 2004 March with the help of thegood monsoon5.5-6.5% in this years growth because QuickTime and aof the late onset of monsoon last TIFF (Uncompressed) decompresare needed to see this picture.summer. (Asian Development Bank)Onset, extent and overall amount ofmonsoon rainfall play a key role 9. Relationship between Indian rice production andIndian monsoon rainfall (Webster et al. 1998) 10. Mechanisms of monsoon1. Difference in heat capacity of land and ocean 11. Mechanisms of monsoonTemperatures over oceans do not change as much as over lands January Surface Air TemperatureQuickTime and a TIFF (Uncompressed) decompressorare needed to see this picture. 12. July Surface Air TemperatureQuickTime and a TIFF (Uncompressed) decompressorare needed to see this picture. 13. Large differences occur over the continents and smallerones over the oceans- an indication of the heat capacityof the surfaceDifference between theJanuary and July surfacetemperature 14. Mechanisms of monsoon July SLP QuickTime and aTIFF (Uncompressed) decompressor are needed to see this picture. 15. Mechanisms of monsoonJanuary SLP QuickTime and aTIFF (Uncompressed) decompressor are needed to see this picture. 16. Mechanisms of monsoon 17. July QuickTime and aTIFF (Uncompressed) decompressor are needed to see this picture.SLPQuickTime and a TIFF (Uncompressed) decompressorare needed to see this picture.Wind 18. QuickTime and aTIFF (Uncompressed) decompressor Surface Wind: January are needed to see this picture.SLPQuickTime and a TIFF (Uncompressed) decompressorare needed to see this picture. Wind 19. ~ Gigantic land-sea breeze ~Warm season L Hcold warm HL wet OceanLandChen et al. 2002 20. Cold season HL warm coldLHdryOcean LandChen et al. 2002 21. Examples of monsoons1. Asian monsoon : the largest monsoonIndia, Sri Lanka, Bangladesh, Indonesia and etc SW monsoonQuickTime and a TIFF (Uncompressed) decompressorare needed to see this picture. QuickTime and aTIFF (Uncompressed) decompressor are needed to see this picture.NE From:http://snrs.unl.edu/ametQuickTime and a TIFF (Uncompressed) decompressorare needed to see this picture.monsoon 351/ogren/monsoons.html 22. The Current system of the Indian Ocean From:Tomczak, Matthias &amp; J Stuart Godfrey: Regional Oceanography: 23. History of Indian summer monsoon rainfall prediction From:http://www.met.rdg.ac.uk/cag/MOL/Introduction/frameindex.htmlMotivated by the Great Indian Drought of1877, the India Meteorological Department isestablished in 1875 for the seasonal forecastof Indian monsoon rainfall.In the early part of the 20th century, Sir QuickTime and aTIFF (Uncompressed) decompressorare needed to see this picture.Gilbert Walker studied the globalteleconnections of monsoon for the monsoonrainfall prediction, which led him to thediscovery of Southern Oscillation.. 24. The factors influencing interannualvariability Indian summer monsoonrainfall Himalayan snow covermore snow higher albedo less T weaker monsoon Soil moisturemore moisture less T weaker monsoon ENSO ? ? 25. 2. North American monsoon ~ Southwest United States monsoon ~ Mexican monsoon ~ Arizona monsoonIncrease in rainfall during summer over the dry regions about 35% of Arizonas annual precipitation about 45% of New Mexicos annual precipitation, about 60% of northern Mexicos annual precipitation 26. QuickTime and aTIFF (Uncompressed) decompressor are needed to see this picture. 27. Mid-to late summer rainfallSeasonal distribution of precipitationacross southwestern max following extremely dryNorth America. Note that northwesternconditionMexico shows thestrongest monsoon signal, whichdiminishes through Arizona,New Mexico, and Nevada. NortheasternMexico and Texasdisplay early summerlate fallprecipitation peaks, while the WestCoast has a dry summer Mediterraneandistribution (vertical axisof all graphs represents 180 mm with 20mm increments). Areassouth of the broken line receive greaterthan 50% of their annualrainfall in July, August, and September(after Douglas et al. 1993). 28. Vertical cross sectionWarm season 29. PredictabilityMonsoon rainfall :Important water resourcesQuickTime and aTIFF (Uncompressed) decompressorare needed to see this picture. Hazards(storms) Monsoon influenced thunderstormUSA today 06/25/2004The North American Monsoon Experiment, announcedFriday, is getting underway this month to help betterunderstand the weather in northwest Mexico and thesouthwestern United States 30. 3. West African monsoonPrecipitationSSTJuneAugust 31. Interannual variability of African monsoonWet 50-60s,Dry 70-90sQuickTime and a TIFF (Uncompressed) decompressorare needed to see this picture. 32. Warmer SST Weaker monsoonGlobal warming Dryer ??</p>