Local Impacts of Global Climate Change

The overarching theme of this blog has so far been to exemplify the climatic characteristics of the city of Bangalore and how certain key variants of the surrounding natural environment, both on the surface and in the atmosphere, amalgamate to construct the cities unique climatic profile. However this profile is not unconditional, it is not a stagnant cyclical pattern that can be predicted with any actual certainty in future trends.  Rather it is a stage in the ever-changing dynamic of planetary meteorological conditions, which has seen vast extremes on both ends of the climatic spectrum.

Through extensive research from an assortment of scientific disciplines, climate variablity is now a near undisputed scientific truth.  Verification occurred by utilizing proxy indicators as tools to determine the historical climatic record through the examination of uninterrupted and preserved mediums, to replicate a direct measurement of climatic conditions. For example the climatic past can be assessed by taking sample cores out of ancient trees.  The cores reveal the annual growth of the tree through examination of the size of each individual ring, providing insight on the annual climatic conditions of that particular site.  Another means in determining conditions are core samples taken from the oceans and large bodies of water.  These sediment samples preserve pollens and other plant materials which are undisturbed from surface conditions and wave actions at water depth.  As important as these core types are for localities and the geologic near-term, core samples taken from ice sheets and glaciers provide the most extensive knowledge of paleoclimatologic conditions. The most prolific of these is the Vostok core taken from Antarctica.  This particular core is the largest of its kind, and provides invaluable data covering over 400,000 years.  This data is derived from encapsulated air bubbles found within the ice, which through analysis determines the atmospheric composition, and greenhouse gas concentrations. The core also provides insight in the amount of precipitation recieved, temperature trends, as well as solar activity on the continent, which is a proven representative of the annual global conditions of the past.  Besides cores, other means of determining historic records include the makeup and deviations of continental margins of the sea floor.  The analysis of the geologic features show historic exposure to wave erosion points, as well as graduated steppes which determine previous historic sea levels.  In conjunction with variation in sea level rise and fall, is the presence and remnants of periods of glaciation. Records can be ascertained both temporally and spatially of glacial periods from examination of present day geological compositions that modified the topography under the glaciers extent.  This is made possible because of the sheer force of an advancing and retreating glacier, which creates and leaves behind stratifications in rock such as granite, and depositions of materials hundreds of miles from their origins.

Whether or not global warming is occurring is not the true emphasis of the debate, rather it is centered upon whom or what is responsible for these trends and to what extent will these trends continue. The source of global warming is basically divide into two factions, those that believe global warming is nothing more than a high point in a natural climatic cycle, which has been occurring since the inception of the earth, and those that believe that the trend is being caused by, or at least, amplified by anthropogenically induced forces.  Those that reason warming is a natural cycle, point to prehistoric records that surpass that of the present, an unreliable temperature record, and an anomalously high instance of solar activity. The opposing view, points to the vast increase in gases such as carbon dioxide, methane, and ozone since the industrial revolution which has led to a greenhouse effect that readily allows solar radiation into the atmosphere, but not out. These opposing views result in models that see warming either continuing on linear path than falling off, or on an exponential path that will completely alter the world’s climate.

As technological advancements are continually made, the present knowledge of historical climate trends continues to be reinforced and advanced.  This also holds true for the detail and scope of global climatic observations of the present day.  Documentation of weather data for most of the “developed” world has been relatively comprehensive for the past century and the “developed”, “developing” and “underdeveloped” world continually improve upon the degree and accuracy of worldwide weather data. This rapid expansion of knowledge has afforded a foundation for an established field that focuses on the prediction of future climatic conditions. However it is a field that is by no means unified, and has been the focus of heated debate for the past several decades.

The above data shows the steep linear trend of CO2 levels found at the Mauna Loa Observatory on the Big Island of Hawaii.  The site is considered nearly ideal as it has limited influence from local pollutants.

Few experts in the field of climatology will deny the fact that the world is presently experiencing an overall warming trend.  Data collected from the past century shows an average global increase in temperature amounting to 0.74 degrees Celsius, with Polar Regions and certain sub-tropical locations increasing over 2 degrees Celsius in the same period.  Adding to the concern is that the warming trend has been most pronounced in the past few decades.  According to the Intergovernmental Panel on Climate Change (IPCC) the period from 1995 to 2006 experienced eleven of the twelve warmest years on record.  More recent data has shown every year of the 2000’s (besides 2008)  making the top ten, and 2010 now tied for the warmest year on record with 2005, and 2011 being the ninth warmest year in recorded observational history. The predictions for Bangalore and the surrounding region range from an minimum increase in mean temperature of 2.7 ̊ Celsius, to a maximum increase of 4.7 ̊ Celsius by the end of the century.

By definition models are smaller scale representations of real world scenarios and systems, which cannot possibly account for the varying components that make up the latter. Climatic models are no different and often produce vastly different results. Some show only slight changes in the environment while other models of worst-case scenarios would see a dramatic increase in extreme weather events, erratic periods of hot and cold, wet and dry, and a rising sea level that would inundate many of the world’s most populous areas.  For our purposes an average will be used to determine the potential direct affects on Bangalore, and the potential affects that may not be as apparent.

  In even the most extreme cases, the possibility of Bangalore being directly affected by rising sea levels is impossible. In a situation where all of the world’s ice sheets and glaciers were melted and the thermal expansion of water is at its maximum, the sea level would be approximately 100 meters higher than present, an amount that is still over 700 meters lower than the cities lowest elevation.  However, a more feasible sea level rise of 20 meters would displace upwards of 400 million people, and a rise of 10 meters would inundate the Indian cities of Calcutta and Mumbai with water, leading to catastrophic social and economic consequences. A recent study by Jawaharlal Nehru University of India projects a 1 meter rise in sea level would displace 7,000,000 Indians.  Nevertheless the models presented by the IPCC predict a maximum rise of 0.59 meters by the end of the century.

The IPCC models for precipitation extensive variability with estimates ranging from a pronounced decline to significant increase.  For the region of South Asia they averaged these models to have a range of plus or minus 11%, which is what is displayed above.  

Another concern of global warming is that of an increase in extreme weather events. The level of confidence in an increase or decrease in magnitude and frequency of such events varies, depending on the source and location.  Either way it could prove disastrous for Bangalore.  A 2009 study conducted by the Scripps Institute of Oceanography, Oregon State University, and the Desert Research Institute of Nevada has correlated abrupt shifts in world climate with a southward shift in seasonal South Asian monsoons.  A significant reduction in vegetation growth was seen when comparing stalagmites in China with equivocal ice core samples, which researchers surmised, was caused by rain falling in the Indian Ocean rather than on the continent, a scenario that would jeopardize the food security of millions.  However recent trends have shown the opposite to hold true.  The intensity, frequency, and magnitude of monsoonal rains have been steadily increasing at a rate of 10% since 1950, frequently leading to catastrophic flooding.   One such example was in 2009, when 240 people were killed just north of the city, and over 100,000 were left homeless after a four day rain event which followed a period of prolonged drought. Flooding in the region would likely be compounded from increased river flows from melting snow pack, leading to a variety of issues, including disease, and agricultural and structural damage.  Another concern in the region is the frequency and magnitude of tropical cyclones, which rarely directly affect the city, but always affect it indirectly.  Though trends show otherwise, many predict an increase of tropical cyclone events, which have historically been some of the world’s worst natural disasters. Finally the last and potentially most devastating effect of global warming may be intense and prolonged heat waves, a scenario that could result in hundreds, if not thousands of immediate deaths per year, as well as an untold amount of deaths from the loss of available food resources.

The above diagram shows the amount of cylcones that have made landfall on the Indian Sub-Continent from the years 1891-2009.  The green represents cyclonic disturbances (31 KM/h to 61 KM/h), the yellow tropical cyclones (62 KM/h to 87 KM/h) and the red representing severe cylclones (88 KM/h and above). Note the trendlines for the above and following graphs.

Unlike the decreasing trend for all types of cyclones that reached landfall, those based in the Arabian Sea have increased overall in the past century.

The cyclones found in the Bay of Bengal are by far the most abundant of the three.  As the second order polynomial trendline shows a peak was seen from the mid 1940's to the mid 1960's, with a steady decrease since.

The nation of India is attentive to these potentially catastrophic outcomes and has made a conscious effort to reduce their impact on climate change.  The country has committed itself to a 20% to 25% reduction in energy usage by 2020 and recently has proposed their 12^th five year plan to reduce GHG emissions.  While the nation currently spends an estimated 2.8% of its gross domestic product on climate change programs, this is still well short of projected required amount needed to fulfill their 2020 goal. Mitigation efforts include the implementation of solar farms, rainwater collection sites, community organized drainage cleaning to reduce the magnitude of floods, and the regrowth of mangrove forests that act as both carbon sinks as well as protective barriers from tropical cyclones.

Though the efforts made by the Indian Government to mitigate and adapt to climate change are noble and well intended programs, the effort may be misplaced. The country is currently ravaged by rampant poverty, much of which is extreme.   This correlates with the high level of illiteracy among its people as well as burgeoning population that susceptible to starvation should food shortages occur from events perpetuated by climatic change.  The country of India and the city of Bangalore are rich in natural and human resources, but if a perpetual cycle of poverty continues to occur, the country and city will always be subjected to an unnecessary risk.

 

 

Sources

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Indian Institute of Science, Centre for Ecological Sciences. (n.d.). Study Area: Bangalore. Retrieved March 07, 2012, from ces.iisc.ernet.in: http://ces.iisc.ernet.in/energy/wetlands/sarea.html

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Intergovernmental Panel on Climate Change. (2012). Managing the Risks of Extreme Events and Disasters to Advane Climate Change Adaptation. Cambridge: IPCC.

Kaspi, Y., & Schneider, T. (2012). Climate Dynamics of Earth and Other Planets. Retrieved April 01, 2012, from Tapio Schneider: http://www.gps.caltech.edu/~tapio/animations.html

Keller, E. A., & DeVecchio, D. E. (2012). Natural Hazards. Upper Saddle River: Pearson Prentice Hall.

Lutgens, F. K., & Tarbuck, E. J. (2007). The Atmosphere: An introduction to meteorology. Upper Saddle River: Pearson Prentice Hall.

Manjaro, C. (2011, October 04). Air Pollution is Stunting India's Monsoon. Retrieved April 02, 2012, from The Watchers: http://thewatchers.adorraeli.com/2011/10/04/air-pollution-is-stunting-indias-monsoon/

McKnight, T. L., & Hess, D. (2008). Physical Geography: A landscape appreciation. Upper Saddle River: Pearson Prentice Hall.

National Data Centre. (n.d.). Monthly Mean Maximum & Minimum Temperature and Monthly Total Rainfall. Retrieved April 30, 2012, from India Meteorological Department: http://www.imd.gov.in/section/nhac/mean/110_new.htm

National Oceanic and Atmospheric Admininstration. (n.d.). Bangalore WMO:43295. Retrieved March 07, 2012, from dossier.ogp.noaa.gov: ftp://dossier.ogp.noaa.gov/GCOS/WMO-Normals/RA-II/IN/43295.TXT

NOAA. (n.d.). Climate Prediction Center. Retrieved April 01, 2012, from National Weather Service: http://www.cpc.ncep.noaa.gov/products/people/Kousky/Lectures/lecture-17-seasonal-cycle-monsoons-conv-zones.ppt.

Nybakken, J. W. (1997). Marine Biology: An Ecological Approach. Addison-Wesley Educational Publishers: Reading.

Poore, R. Z., Willams Jr., R. S., & Tracey, C. (2000). Sea Level and Climate. Retrieved May 05, 2012, from USGS: http://pubs.usgs.gov/fs/fs2-00/

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Sethi, N. (2012, April 30). India to Pump in Rs 2 lakh cr in 12th Plan to Save Climate. Retrieved May 05, 2012, from Times of India: http://articles.timesofindia.indiatimes.com/2012-04-30/global-warming/31506507_1_national-action-plan-climate-change-green-india-mission

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Singh, M. (2009, April 11). Cows with Gas: India's Global-Warming Problem. Retrieved May 05, 2012, from Time: http://www.time.com/time/world/article/0,8599,1890646,00.html

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Srinath, P. (2012, March 24). Climate Data in India: Open and Closed. Retrieved April 30, 2012, from slideshare.net: http://www.slideshare.net/PavanSrinath/climate-data-in-india-open-and-closed

University of Wisconsin-Madison. (n.d.). Air Masses and Fronts. Retrieved April 01, 2012, from cimss.ssec.wisc.edu: http://cimss.ssec.wisc.edu/wxwise/class/frntmass.html

Withgott, J., & Brennan, S. (2008). Environment: The Science Behind the Stories. San Francisco: Pearson Benjamin Cummings.

Historical Climatology of Bangalore and the Growth of the City

As with all the locations of the world, an accurate description of a localities weather and climate regime must consider the various scales that influence it and make each individual location unique. In meteorology, scales are distinguished spatially as either micro, meso, or macro, from smallest to largest respectively, and the latter of which will be discussed in the next post.  So far, this blog has focused extensively and nearly exclusively on the meso (regional) scale of the Indian subcontinent and surrounding environments.  This includes discussion of Bangalore’s position in relation to the Indian Ocean and the Asian Continent, as well as the ITCZ and the Himalayan Mountains. Combined, these factors contribute to a generalized regional weather system, which is often portrayed on maps using classification systems such as Koppen-Geiger. However, each specific location has its own unique weather and thus climate.  These variations’s can be seen from city to city, city to rural, or wholly within the city itself, at the micro-scale.  In the case of Bangalore the most pronounced factor that is currently changing, as well as differentiating its climate from its neighbors, is the near exponential population growth and the subsequent expansion of the city proper. Known as an urban heat island effect, the city itself tends to be warmer than the surrounding environments. Also precipatation tends to be slighltly higher on the windward side of the city, a situation which would not have occured otherwise. The cause behind urban heat islands is belevied to be from an increase in the albedo of built environments, a decrease in evapotranspiration, and an increase in environmental air pollutants.

The above records are from the Indian government's Ministry of Home Affairs, the branch which is responsible for the decadal census of the country.  This type of growth is seen throughout the country  and India is expected to surpass China sometime in the next couple of decades as the most populous country in the world.  The city of Bangalore has several times been the fastest growing major city in the country and consistently been among the fastest growing cities in the world.

The above graph is the historical mean high and low temperatures for Bangalore along with the annual precipitation. Though high temperatures have remained relatively consistent, the mean low has increased significantly from 1901 to 2000. Also take note at the extreme variation in precipitation, from over 100 mm in one year to a half a decade straight of no recordable amount.

The historical records for July show an upward trend in both the mean highs and mean lows for the month and with an almost 1.5 degree Celsius increase in the average low over the century long period.  It should be noted that the reason for the lack of information of the most recent decade is the propriety stance of the Indian Meteorological Department.  Generalized and often incomplete information can be obtained from mostly US and European agencies and entities, but the inconsistent nature within and between these highly regarded meteorological centers has left me no choice but to omit their data.  These policies are currently being questioned by academia, businesses, and individuals within the country and abroad.  A slide show can be found at the end of the post for further information and action currently taking place.

The most widely used climate classification system, the Koppen-Geiger system was created in the latter part of the 19th century and has been expanded upon several times since.  In terms of scale, at best it could be considered effective on the meso level, however should probably be only considered at the macro-scale as seen above.

Zooming into the regional meso-scale it can be seen that Bangalore falls along the border of Highland Subtropical (CWb) and Humid Subtropical (CWa), however other sources have placed the city in a warm semi arid or tropical wet-dry regime. These definitive lines and descriptions are why it is important to consider all scales when describing a specific location.  As mentioned before historical analysis has shown that the city center has different weather patterns than the surrounding environments, a discrepency that continues to increase with continual urbanization.  

Sources:

GOOGLE EARTH. (n.d.).

Indian Institute of Science, Centre for Ecological Sciences. (n.d.). Study Area: Bangalore. Retrieved March 07, 2012, from ces.iisc.ernet.in: http://ces.iisc.ernet.in/energy/wetlands/sarea.html

Iyer, N. K., Kulkarni, S., & Raghavaswamy, V. (2007). ECONOMY, POPULATION AND URBAN SPRAWL A COMPARATIVE STUDY. Urban Population, Development and Environment Dynamics in , 1-37.

Kaspi, Y., & Schneider, T. (2012). Climate Dynamics of Earth and Other Planets. Retrieved April 01, 2012, from Tapio Schneider: http://www.gps.caltech.edu/~tapio/animations.html

Keller, E. A., & DeVecchio, D. E. (2012). Natural Hazards. Upper Saddle River: Pearson Prentice Hall.

Knox, P. L., & Marston, S. A. (2010). Human Geography: Places and Regions in Global Context. Upper Saddle River: Person Prentice Hall.

Lutgens, F. K., & Tarbuck, E. J. (2007). The Atmosphere: An introduction to meteorology. Upper Saddle River: Pearson Prentice Hall.

Manjaro, C. (2011, October 04). Air Pollution is Stunting India's Monsoon. Retrieved April 02, 2012, from The Watchers: http://thewatchers.adorraeli.com/2011/10/04/air-pollution-is-stunting-indias-monsoon/

McKnight, T. L., & Hess, D. (2008). Physical Geography: A landscape appreciation. Upper Saddle River: Pearson Prentice Hall.

National Data Centre. (n.d.). Monthly Mean Maximum & Minimum Temperature and Monthly Total Rainfall. Retrieved April 30, 2012, from India Meteorological Department: http://www.imd.gov.in/section/nhac/mean/110_new.htm

National Oceanic and Atmospheric Admininstration. (n.d.). Bangalore WMO:43295. Retrieved March 07, 2012, from dossier.ogp.noaa.gov: ftp://dossier.ogp.noaa.gov/GCOS/WMO-Normals/RA-II/IN/43295.TXT

NOAA. (n.d.). Climate Prediction Center. Retrieved April 01, 2012, from National Weather Service: http://www.cpc.ncep.noaa.gov/products/people/Kousky/Lectures/lecture-17-seasonal-cycle-monsoons-conv-zones.ppt.

Nybakken, J. W. (1997). Marine Biology: An Ecological Approach. Addison-Wesley Educational Publishers: Reading.

Peel, M. C. (n.d.). Spain. Retrieved April 30, 2012, from familypedia: http://familypedia.wikia.com/wiki/Spain

Srinath, P. (2012, March 24). Climate Data in India: Open and Closed. Retrieved April 30, 2012, from slideshare.net: http://www.slideshare.net/PavanSrinath/climate-data-in-india-open-and-closed

University of Wisconsin-Madison. (n.d.). Air Masses and Fronts. Retrieved April 01, 2012, from cimss.ssec.wisc.edu: http://cimss.ssec.wisc.edu/wxwise/class/frntmass.html

Ward, A. D., & Trimble, S. W. (2004). Environmental Hydrology. Boca Raton: CRC Press.

Withgott, J., & Brennan, S. (2008). Environment: The Science Behind the Stories. San Francisco: Pearson Benjamin Cummings.

Climate data in india - Open and Closed

View more PowerPoint from Pavan Srinath

The Extent and Affect of the Monsoon's Through Comparing and Contrasting

As alluded to in the two previous posts of this blog, the climate conditions of Bangalore are formed by the cities relative position to the equator and the topographical makeup of the surrounding environment.  These geographical components create the air masses which dictate the climatic conditions of the region and are responsible for the monsoon winds that have such a significant impact throughout the seasons of the city.  So one would assume any pronounced differences in either the latitude of an area or a differing topographical regime would drastically change the climatic conditions affecting an area.  This is indeed usually the case; however the magnitudes of the monsoons that affect the Indian subcontinent tend to neutralize the extremities of these changes. A primary example of this is seen by comparing and contrasting the city of Bangalore, India with that of Kathmandu, Nepal.  The two cities are within 500 meters of each other in terms of elevation, but are found on the opposite ends of the Indian Subcontinent (from the northeast to the southwest), covering a distance of over 1,800 kilometers. With Bangalore residing within the tropic of cancer at 13 ̊ North latitude and Kathmandu within three degrees of the Horse Latitudes of 30 ̊ North, expectations of dramatic temperature and precipitation differentials should be pronounced.  However in this scenario it is not the case.  Kathmandu is unique in that it is positioned on the windward side of the world’s highest mountain range, the Himalayas. As illustrated below the sheltering dynamic surrounding the city along with the  pronounced force of the monsoons, has a dramatic effect on the cities climate. 

Map showing the location of the two cities in relation to each other.

Climate

The graphic above shows a comparison between the average monthly mean, high and low temperatures of the two cities.  The difference is slight in overall temperatures considering all factors, while near identical in the summer months of June, July, and August.  The most pronounced variation can be seen in the average monthly lows during the winter months.



While both cities high precipiation totals from the months of May to October and relativily low totals for the remainder of the year can be attributed to the monsoon winds and associated air masses, Kathmandu recieves vastly more because of the surronding topography.  The city lies on the windward side and at the base of the Himalayas.  This positioning subjects the city to copious amounts of rain from orographic lifting of the warm moist air mass from the Indian Ocean during the rainy season. 

 



Topography

Bangalore: As the above photograph confirms, the city lies on a relatively flat terrain with only slight variations found within the city proper and surrounding region.

Kathmandu: As seen the topography of the city is much more dramatic than that of Bangalore.  Sitting within the foothills of the Himalayas has a significant impact on the climate of the city.  The mountains can be seen faintly towering in the background. 

A map showing the total annual rainfall worldwide. A profound difference can be seen in the amount of precipitation received in southeast Asia when compared to the vast deserts of the Middle East in the Northern African Sahara, all which are approximately at the same latitude. 

SOURCES:

GOOGLE EARTH. (n.d.).

Indian Institute of Science, Centre for Ecological Sciences. (n.d.). Study Area: Bangalore. Retrieved March 07, 2012, from ces.iisc.ernet.in: http://ces.iisc.ernet.in/energy/wetlands/sarea.html

Kaspi, Y., & Schneider, T. (2012). Climate Dynamics of Earth and Other Planets. Retrieved April 01, 2012, from Tapio Schneider: http://www.gps.caltech.edu/~tapio/animations.html

Kathmandu Climate Guide. (n.d.). Retrieved April 16, 2012, from Kathmandu: http://www.climatetemp.info/nepal/

Keller, E. A., & DeVecchio, D. E. (2012). Natural Hazards. Upper Saddle River: Pearson Prentice Hall.

Lutgens, F. K., & Tarbuck, E. J. (2007). The Atmosphere: An introduction to meteorology. Upper Saddle River: Pearson Prentice Hall

Manjaro, C. (2011, October 04). Air Pollution is Stunting India's Monsoon. Retrieved April 02, 2012, from The Watchers: http://thewatchers.adorraeli.com/2011/10/04/air-pollution-is-stunting-indias-monsoon/

McKnight, T. L., & Hess, D. (2008). Physical Geography: A landscape appreciation. Upper Saddle River: Pearson Prentice Hall.

National Oceanic and Atmospheric Admininstration. (n.d.). Bangalore WMO:43295. Retrieved March 07, 2012, from dossier.ogp.noaa.gov: ftp://dossier.ogp.noaa.gov/GCOS/WMO-Normals/RA-II/IN/43295.TXT

NOAA. (n.d.). Climate Prediction Center. Retrieved April 01, 2012, from National Weather Service: http://www.cpc.ncep.noaa.gov/products/people/Kousky/Lectures/lecture-17-seasonal-cycle-monsoons-conv-zones.ppt.

Shreshta, V. P. (2007). A Concise Geography of Nepal: Kathmandu. Mandal Publications.

University of Wisconsin-Madison. (n.d.). Air Masses and Fronts. Retrieved April 01, 2012, from cimss.ssec.wisc.edu: http://cimss.ssec.wisc.edu/wxwise/class/frntmass.html

Ward, A. D., & Trimble, S. W. (2004). Environmental Hydrology. Boca Raton: CRC Press.

The Role of Air Masses and the Intertropical Convergence Zone on Seasonal Climatic Variations

The influence of an air masses is regarded as one of the most fundamental elements of weather and climate regimes, determining an area’s associated temperature and precipitation development.   Defined, an air mass is an exceedingly large mass of air that shares a relatively homogeneous temperature and moisture content at any given altitude, or horizontal direction, that is a part of the mass. Though small variations do exist within these masses, as to be expected, as they usually exceed over 1,500 kilometers. As the mass moves away from its point of origin, the characteristics of that location are transferred to the locations it travels over.  Movements of these masses are driven from pressure differentials from latent heat flux on the surface, for Bangalore this movement coincides with that of the intertropical convergence zone (ITCZ).  Masses are classified under two categories, their relation to the equator, which consists of arctic, polar, tropical, or equatorial; and their topographical surface of their origin, either maritime over large bodies of water, or continental over landmasses. For instance in the case of Bangalore a continental polar (cP) and continental arctic (cA) mass is predominant in the fall and winter, which produces dry conditions, while a maritime equatorial (mE) is dominant in the spring and summer, bringing moister conditions. Though seemingly vastly different, these two masses do hold similarities, like most masses they are formed on relatively flat, uniform surfaces with stagnant surface circulation. The complexity of these topics can be quite extensive, but can be somewhat clarified by examining the following graphics.

The graphic above shows the approximate region of origin for the major air masses of the world. Of these, two have a significant impact on the precipitation characteristics of Bangalore, the continental polar and continental arctic masses originating in Siberia, and the maritime equatorial mass over the Indian Ocean.  These masses traverse in and out of the Indian subcontinent, largely because of three main reasons. First the surface temperature differential shaped by the seasons, followed by the difference in specific heat of water molecules and molecules incorporating the makeup of land surfaces, and finally the influence of the intertropical convergence zone.  

The intertropical convergence zone (ITCZ) is a band that represents the convergence of the NE and SE trade winds, within a close proximity to the equator.  Also referred to as the equatorial low, this band brings high levels of precipitation from the release of latent heat from the persistent warm rising air.  The ITCZ loosely follows the sub-solar point over India, which is representative of the seasonal shift between the wet and dry. As seen above the ITCZ is deep within the the Indian Ocean in January, drawing in the cool dry continental air from the northern Asian continent.  The opposite is true in July, as the land is warmed more rapidly than the water from the ocean, it draws in the humid unstable air, resulting in heavy precipitation. 

The above graphics help demonstrate the typical direction and extent of the ITCZ and how and where it affects Bangalore.

The above map shows the amount of precipitation across the world in the month of January.  As can be seen the India receives minimal amounts during this period. as the dry continental Siberian mass influence the convective and thermal forces above the land.  The temperature however remains relatively mild due to Bangalore's positioning within the tropics.

A vastly different scenario develops in Bangalore soon after the spring equinox when heavy precipitation occurs from the end of April to the beginning of October. As can be seen above the movement of the maritime equatorial mass from the Indian Ocean moves north, inudating the land with some of the highest precipitaion totals on the entire planet.

Another factor that accounts for the amount of precipitation and the movements and development of air masses within the atmosphere in Bangalore, is the Indian Ocean Oscillations. Similar to the movements of El Nino and La Nina oscillations, except to a much lesser extent, depending on the phase rainy or drought conditions can fall upon Bangalore or the Indian sub continent as a whole.

Current Atmospheric Conditions

Bibliography

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Kaspi, Y., & Schneider, T. (2012). Climate Dynamics of Earth and Other Planets. Retrieved April 01, 2012, from Tapio Schneider: http://www.gps.caltech.edu/~tapio/animations.html

Keller, E. A., & DeVecchio, D. E. (2012). Natural Hazards. Upper Saddle River: Pearson Prentice Hall.

Lutgens, F. K., & Tarbuck, E. J. (2007). The Atmosphere: An introduction to meteorology. Upper Saddle River: Pearson Prentice Hall.

Manjaro, C. (2011, October 04). Air Pollution is Stunting India's Monsoon. Retrieved April 02, 2012, from The Watchers: http://thewatchers.adorraeli.com/2011/10/04/air-pollution-is-stunting-indias-monsoon/

McKnight, T. L., & Hess, D. (2008). Physical Geography: A landscape appreciation. Upper Saddle River: Pearson Prentice Hall.

National Oceanic and Atmospheric AdmininstrationBangalore WMO:43295. Retrieved March 07, 2012, from dossier.ogp.noaa.gov: ftp://dossier.ogp.noaa.gov/GCOS/WMO-Normals/RA-II/IN/43295.TXT

NOAA. (n.d.). Climate Prediction Center. Retrieved April 01, 2012, from National Weather Service: http://www.cpc.ncep.noaa.gov/products/people/Kousky/Lectures/lecture-17-seasonal-cycle-monsoons-conv-zones.ppt.

Petersen, C. (n.d.). Education: GEEBIT. Retrieved March 07, 2012, from GISS Institute on Climate and Planets: http://icp.giss.nasa.gov/education/geebitt/

University of Wisconsin-Madison. (n.d.). Air Masses and Fronts. Retrieved April 01, 2012, from cimss.ssec.wisc.edu: http://cimss.ssec.wisc.edu/wxwise/class/frntmass.html

Ward, A. D., & Trimble, S. W. (2004). Environmental Hydrology. Boca Raton: CRC Press.

Introduction of Climatic Characteristics

     The city of Bangalore is geographically located within the northern tropics, and is classified under the Koppen classification system as a tropical savanna climate (Aw) or more specifically a tropical wet and dry climate (As).  This classification is distinguished by two distinct periods, a relatively dry winter followed by a wet period over the summer and early fall.  The seasons of the city are thus defined by the amount of precipitation. The dry season is from December through February, followed by the summer season from March to to May, a monsoon season which experiences most of the overall rainfall occurs  from June to September, and finally the post monsoon season marked by a variable climate, which lasts from October to November .   This climate does differ from the regions directly to the north which tend to have a drier climate and are classified as subtropical steppes(Bsh), and to the south of the city which have a humid subtropical (Cwa). Combined these climates represent the entirety of the southern portion of the Indian sub-continent.  An area that generally experiences mild to warm weather and has a topography which is characterized by relatively flat plateaus,  the Bangalore metro area has elevations ranging between 720 and 962 meters.
     This blogs intent is to explore these climatic characteristics, how the regions geography plays a role in the development of these characteristics and how the cities recent population explosion factors in on as a precursor for potential anthropogenically induced climate change. (Source: 1,2,3,4)

Temperature Data

     The above graph and table illustrate the high, low, and average monthly temperature of Bangalore.  Due to the cities geographical location (which lies within the tropics and is positioned inland of the  Indian subcontinent) the temperature of the city is generally mild and relatively consistent. The sub-solar point of the earth occurs over the city twice a year, on March 25th and September 16th in 2012.(Source: 3,4,5)

Precipitation Data

     The above graph and table illustrate the average monthly precipitation and relative humidity of Bangalore.  The primary force driving the frequency and magnitude of rainfall events within the city is the monsoon season associated with the region. Often falsely describe as precipitation phenomenon, a monsoon event is actually global circulation event associated with winds.  Monsoons generate a pronounced pressure gradient that is formed from a differential in the surface heating properties of land (the massive Asian continent) in relation to water (the adjacent Indian Ocean), thus creating a significant seasonal variation.  In the case of the Indian subcontinent, which lies within the tropics, the intertropical convergence zone seasonally travels the entire expanse of the region. In the summer months this creates a high pressure system inland which draws moisture from the low pressure system in the Indian Ocean, resulting in heavy precipitation. The exact opposite holds true in the winter months, as the directional wind flow comes from the cold Asian continent bringing in dry high pressure systems over the city.  Exacerbating this situation is the positioning of the world's highest mountain range, the Himalayas, which promote orographic lift.  These factors combined create the produce the most noteworthy precipitation change on Earth. (Source 2,3,4,5)

GEEBIT

     The global equilibrium energy balance tinker toy (GEEBIT), is a spreadsheet device that uses built in computations that estimate the effects of earth's regulatory characteristics on the overall mean surface temperatures of the planet. Developed by NASA as an educational tool, the program considers such critical factors as planetary distance, albedo, and the greenhouse effect, all which can be manipulated to demonstrate the importance of planetary energy budgets. For example, the above spreadsheet shows earth's present energy balance which creates an average surface temperature of 15 C.  However if the average albedo of planet was raised by 0.10 to 0.406, the planetary surface temperature would drop to 4 C, conversely if the albedo was lowered by 0.10 to 0.206 it would rise to 24.8 C.  Another example is the greenhouse factor. An increase of 10% would take the planetary temperature from 15 C to 17.7 C, while a decrease would lower global surface temperatures to 12.1 C.  Of course these are all just estimations that cannot account for all of the potential positive feedback mechanisms which would occur.  Bangalore, like the world over, would see drastic changes in climate and weather, likely producing more variable and severe weather patterns, as well as an eventual overall biospheric change.   (Source: 6)

Bowen Ratio

     The bowen ratio is a mathematical formula used to determine the percentage of radiant heat that goes into either sensible heat or  the amount that go into latent heat.  Starting at a base of 1, where there is an equal distribution of available radiation between the two fluxs, is the amount which is near representative of  the  balance of the planet as a whole.  The ratio is lowered when more radiant heat is used for latent heat, resulting in moister conditions,  the opposite holds true when more of the energy goes toward sensible heat. The differences in the results of the ratio is determined by the available moisture content within the atmosphere as well as the amount of evapotranspiration occurring on the surface. Generally speaking more heat goes into latent heat around coastal areas (causing moister conditions), whereas continental regions tend to be drier, were more energy goes into sensible heat.  Bangalore's geographical position is influenced by both, depending on the season.   Bangalore likely has a ratio around or slightly above 1.2 in the winter months and early spring and around 0.45 from late spring until the late fall.  This discrepancy can be attributed to the influx of moisture during the monsoon seasons.  (4,7)

Water Conservation in Bangalore

Sources: 

1.  Indian Institute of Science, Centre for Ecological Sciences. (n.d.). Study Area: Bangalore. Retrieved March 07, 2012, from ces.iisc.ernet.in: http://ces.iisc.ernet.in/energy/wetlands/sarea.html

2.  Keller, E. A., & DeVecchio, D. E. (2012). Natural Hazards. Upper Saddle River: Pearson Prentice Hall.

3.  Lutgens, F. K., & Tarbuck, E. J. (2007). The Atmosphere: An introduction to meteorology. Upper Saddle River: Pearson Prentice Hall.

4.  McKnight, T. L., & Hess, D. (2008). Physical Geography: A landscape appreciation. Upper Saddle River: Pearson Prentice Hall.

5.  National Oceanic and Atmospheric Administration. (n.d.). Bangalore WMO:43295. Retrieved March 07, 2012, from dossier.ogp.noaa.gov: ftp://dossier.ogp.noaa.gov/GCOS/WMO-Normals/RA-II/IN/43295.TXT

6.  Petersen, C. (n.d.). Education: GEEBIT. Retrieved March 07, 2012, from GISS Institute on Climate and Planets: http://icp.giss.nasa.gov/education/geebitt/

7.  Ward, A. D., & Trimble, S. W. (2004). Environmental Hydrology. Boca Raton: CRC Press.