Climate change refers to any significant change in measures of climate (such as temperature, precipitation, or wind) lasting for an extended period (decades or longer).

Climate change may result from:

natural factors, such as changes in the sun's intensity or slow changes in the Earth's orbit around the sun;

natural processes within the climate system (e.g. changes in ocean circulation);

human activities that change the atmosphere's composition (e.g. through burning fossil fuels) and the land surface (e.g. deforestation, reforestation, urbanization, desertification, etc.)

D histOry behind it…

1827- Fourier hypothesizes greenhouse effect

1860- Tyndal identifies CO2 n water vapor as heat trapping gases

1896-Aranhius calculates earth warming from gases n predicts future warming from doubling n quadrupling CO2

1930-Calandar shows correlation of temperature n CO2

1958- Keeling begins direct measurement of CO2 in atmosphere

1980 to 2004 –evidence accumulates

Natural ProcessesCause variations in the earth’s climate over

hundreds of thousands of yearsSome are affected by human activity :

greenhouse effectInter-related and involve in complex feedback

mechanism : either enhance or dampen the climate changes.

Extra-terrestrial factorsThe sun’s activity variation:The sun can vary in its intensity or total

irradiance, which would result in direct heating or cooling of the earth.

Changes in the intensity of ultraviolet radiation may alter ozone production in the stratosphere, leading to atmospheric heating.

Earth’s orbit changes:Intersection of 3 natural variations in the

shape of the earth’s orbit, axial tilt, and precession or axial wobble change the amount of solar radiation heating the earth.

These variations are called Milankovitch cycles.

Within the earthVolcanism• Produce changes in the earth's radiative

balance on timescales of years to decades.• Strong volcanic eruptions can send

particulates  and sulphate aerosols high into the atmosphere : the aerosols remain for 2-3 years.

• Large transitory increase in aerosol concentrations- significant influence on the earth's climate in the short term.

Continental and mountain drift As a respond to the drag of molten rock

circulating in the deep parts of the earth's crust below.

Process of plate tectonics.Considered constant since it’s very slow

process.

Earth’s surfaceReflectivity Bright surfaces reflect more heat and light

than darker ones. Thus, absorb less heat.Varies mainly through changes in cloudiness,

snow and ice cover, vegetation cover and land use. 

Ocean-atmosphere heat exchange• Continuous process• Oceans can hold much more heat than the

atmosphere.• To buffer temperature changes in the

atmosphere, while ocean circulation redistributes heat around the globe and influences regional climates. 

• Ability to absorb carbon dioxide from the atmosphere-important greenhouse gas sink & causing ocean acidification.

Atmospheric compositionGreen house gases are largely transparent to

the incoming solar radiationBut strongly absorb the infrared radiation

emitted from the ground.Prevents the movement of some of this

infrared energy into space - warms the earth, and is the natural green house effect.

Anthropogenic (Man-made)Increasing evidence that man activities

directly influenced climate changeIncreasing green house gases – leads to

altered atmospheric composition.Changing the earth’s surface reflectivity

Enhance green house effect Combustion of fossil fuels releasing green

house gases.Clearing of forest releasing carbon dioxide

through increased biomass decay.Deforestation, soil tillage, and land

degradation releasing carbon from land system.

Green house Effect

Greenhouse GasesThe main greenhouse gases emitted or

generated by human activities are:CARBON DIOXIDE (CO2).METHANE (CH4).HALOCARBONS (including CFCs)NITROUS OXIDE (N2O).OZONE (O3).

All green house gases concentrations have all grown steeply in the last century relative to earlier levels

It is accompanied by increased radiative forcing – increase the warming of the earth’s surface.

Trends in the main greenhouse gases concentrations in the atmosphere in the last 1000 years

Positive forcings lead to warming of climate and negative forcings lead to a cooling.

Changes the earth’s surface reflectivityFossil fuel combustion, industrial processes,

and biomass burning release aerosols and other pollutants into the atmosphere, changing its capacity to reflect or absorb solar radiation. 

Deforestation, agricultural practices and urbanization

Land use change• May reduce or promote the ability of soil and

vegetation to absorb, store and release carbon and carbon dioxide.

• Soil tillage and deforestation - reduce the land's capacity to absorb carbon dioxide.

• Deforestation also reduces the ability of soils to retain moisture and may make it harder for rainwater to infiltrate & exacerbating erosion.

• The decay of plant biomass (in land clearing) contributes to CO2 and methane emissions.

Anthropogenic changes in land cover

From 1990-2010, what would you expect in term of anthropogenic earth’s surface changes?

CLIMATE CHANGE

Direct impactsThe direct health effects would include changes in mortality and morbidity from heatwaves and thermal stress.

Since extremes of heat and cold affect elderly and sick people in particular, the average impact on life expectancy may not be large.

Direct impactsOther direct effects would include:

altered concentrations of aeroallergens (such as spores and moulds) → affects respiratory health

Thinning of the ozone layer by the photochemical reactions that are sensitive to temperature

Storms, floods and other different health consequences of an altered tempo of extreme weather events

Direct impacts

Indirect impactsUsually resulted from disruption of the complex ecological system

Greater consequence and more concerning about health

E.g.:Changes in activity of vector borne diseaseChanges in person-to-person infection transmissionChanges in nutritional and health consequences in

agricultural productivityVarious consequences of rising sea levelsMovements of population → affects the public healthRegional conflicts over food and water in shortages

Indirect impacts

CLIMATE CHANGE

INFECTIOUS DISEASESVector borne diseases:

MalariaDengueTrypanosomiasisViral encephalitisSchistosomiasis Etc.

INFECTIOUS DISEASESIncreased temperatures and changed rainfall

would affect:range;proliferation;behaviour of the vectors and intermediate hosts;viability;maturation rates of the agents.

Increased risk in endemic areas, tropical and subtropical countries due to poor public health defense

INFECTIOUS DISEASESMalaria

Approximately 45% of the world's population currently live in zones that are defined climatically as areas of potential malaria transmission

Assuming that other factors remain constant this would increase to around 60% towards the end of the next century

Malaria is moving to higher altitudes → affect highland populations who are currently protected

INFECTIOUS DISEASESDengue

Caused by the world’s most prevalent mosquito-borne virus

Transmitted principally by Aedes aegypti and Aedes albopictus

These mosquitoes are strongly affected by ecological and human drivers Variability in temperature Moisture Solar radiation

INFECTIOUS DISEASESViral encephalitis borne by ticks: occurs

in parts of western Europe and Scandinavia and is sensitive to the climate

Leishmaniasis: currently endemic in the rural Mediterranean region of Europe and in the eastern Mediterranean. Climate change may extend the habitat of the sandfly vector northwards

INFECTIOUS DISEASESLyme disease: caused by the

spirochaete Borrelia burgdorferi, transmitted in Europe and the northeastern United States by the tick Ixodes ricinus. Temperature influences the tick's life cycle of three stages (larvae, nymphs, adults) and, hence, the probabilityo f transmission of the spirochaete.

FOOD PRODUCTION, HUNGER & MALNUTRITIONClimate change would affect the production

of food, especially that of cereal cropschanges in temperature, soil moisture, carbon

dioxide "fertilisation," and pest and pathogen activity

 tropical and subtropical countries would be most affected, especially poor and economically underdeveloped populations who would be unable to offset reduced agricultural yields by trade

FOOD PRODUCTION, HUNGER & MALNUTRITIONLong term climatic changes, however, might

have a net negative impact on world agriculture

Hunger and malnutrition → increase the risk of infant and child mortality → physical and intellectual stunting

Water supplies → Tensions over shortages of fresh water, especially in low to middle latitude locations

WHO estimated mortality (per million people) attributable to climate change by the year 2000

What is projection of climate change?

-examination of scenarios of possible climate change that can come about because of continuing emissions of greenhouse gases and other radiatively important substances.

The amount and speed of future climate change will ultimately depend on :

Whether greenhouse gases and aerosol concentrations increase, stay the same or decrease.

How strongly features of the climate (e.g. temperature, precipitation and sea level) respond to changes in greenhouse gas and aerosol concentrations.

How much the climate varies as a result of natural influences (e.g. from volcanic activity and changes in the sun’s intensity) and its internal variability (referring to random changes in the circulation of the atmosphere and oceans).

Tools to make projection of climate change :

consists of three-dimensional dynamical and physical models of the atmosphere, ocean, land surface and cryosphere (areas of Earth where the surface is frozen), which are coupled together and run on powerful supercomputers = “climate models”

There are many models around the world, all with different formulations, strengths and weaknesses – which make the climate change projections uncertain.

Since it is difficult to choose the best model, Intergovernmental Panel of Climate Change (IPCC) has defined four levels of certainty in projections :

Virtually certain to very likely : established projections which most models agree on

Very likely : new projections which most newer models agree on

Likely : new projections which a smaller number of models agree on

Medium likelihood : models are unresolved but changes are physically plausible

Examples Virtually Certain to Very Likely

Changes : Northern Hemisphere snow cover

and sea-ice extent decrease. Global mean water vapor,

precipitation and evaporation increase. An increase in temperature implies the atmosphere can hold more water vapour leading to a more vigorous global hydrological cycle.

The intensity of rainfall events increases, and this increase is greater than that expected from a simple change in the mean rainfall.

The mean state of the tropical Pacific becomes more “El Nino-like” with greater warming in the east in comparison with the west and a corresponding eastward shift in precipitation.

Interannual variability in the northern summer monsoon increases.

Very Likely Changes :The direct radiative effect of sulphate

aerosols (a reduction in solar heating) leads to a reduction in mid 21st century warming in comparison to the case with no direct effect.

An increase in temperature and humidity leads to greater values of the “heat index” – a measure of discomfort on hot days.

Likely Changes :

Extremes of warm temperatures are more likely to occur in regions of reduced soil moisture and extremes of cold temperatures are more likely to occur in regions of snow and ice retreat.

Medium Likelihood Changes :

Some models show an increase in the amplitude and frequency of El Nino events, but there is no consensus across models.

Global Mean Changes It is estimated that the range of global mean

temperature warming at 2100 (relative to 1990) is 1.4°C to 5.8°C

Some of the effects of this warming are:- Rising of sea level by 3.5 to 34.6 inches

between 1990 and 2100- Changes in precipitation patterns- Serious human health problems – d/t

increasing heat stress, worsening air pollution, declining water quality, etc.

PreventionEducate socities

Public ForumsInteractive Sessions (School students)Publication of educational material Production of a video documentary

(Danida Funded Project, MMCC)

PreventionMotivate as many sectors to positive action on

climate changes as a result of an effective advocacy and awareness campaign.

Stakeholders Workshop/Seminars NGOs Briefings & TrainingClimate Change Seminars Partnerships

(Danida Funded Project, MMCC)

NEDO’s activity for reducing GHG emission

NEDO- New Energy and Industrial Technology Development Organization

NEDO has presented their planned to reduce Green House gas emission in CTI INDUSTRY JOINT SEMINAR, February 25, 2005,Beijing, CHINA .

NEDO’s activity for reducing GHG emissionAmong their plans:

Advanced industrial furnace *furnace: enclosed chamber in which material

can be heated to very high temperatureDevelopment technology for new energy

conservation systemProgram for development of photovoltaic

generation system

NEDO’s activity for reducing GHG emission

Advanced industrial furnace

NEDO’s activity for reducing GHG emissionPhotovoltaic

is a method of generating electrical power by converting solar radiation into direct current electricity using semiconductors that exhibit the photovoltaic effect(wikipedia)

Advantage: recycle solar energy into electricity supply

Warming Seas Threaten Coral Off Indonesia

The New York Times, By JOHN COLLINS RUDOLF August 19, 2010, http://green.blogs.nytimes.com/2010/08/19/warming-seas-threaten-coral-off-indonesia/

According to marine biologists, large swaths of coral reef in the Andaman Sea off the north coast of Sumatra are now up to 80 percent bleached, with more colonies expected to die off in the coming months

to a spike in sea temperatures in May that left waters in the area about 7 degrees Fahrenheit above average

A similar threat to reefs in other areas which were recorded in Sri Lanka, Thailand, Malaysia and other parts of Indonesia.

Malaysia closes dive sites29 July 2010, Divernet, http://www.divernet.com/home_diving_news/550119/malaysia_closes_dive_sites.html

The Malaysian Government has closed twelve key reef sites until the end of October

The closures include the diving destinations of Tioman and Redang islands, due to damage caused by a combination of climate change and tourism

Large areas of coral have been showing signs of dying off due to a rise in sea temperature, currently some 2°C above normal levels at 31°C

Climate change threatens migratory birds

BY JAY ROOT, ASSOCIATED PRESS, THURSDAY MAR 11, 2010, http://www.salon.com/wires/us/2010/03/11/D9ECO29O1_us_climate_birds/index.html

oceanic birds, such as petrels and albatrosses, are at particular risk from a rapidly changing marine ecosystem and rising sea levels

Seabirds tend to have low reproductive potential and often nest on islands that can be inundated by rising sea levels, changes in water chemistry and other disruptions to the marine ecosystem

Pakistani floods reportedly triggered by climate change

By Amjad Bashir SiddiqiFor CentralAsiaOnline.com, 2010-08-19, http://centralasiaonline.com/cocoon/caii/xhtml/en_GB/features/caii/features/

pakistan/2010/08/19/feature-01

The super-floods that swept from Kashmir and Khyber Pakhtunkhwa down to the southern end of Sindh are a harbinger of global climate change’s influence on South Asia

This year’s “extreme and unusual weather” represents global climate change, said Director General of Pakistan Meteorology Department, Dr. Qamar-uz-Zaman Chaudhary

Climate change threatens Asia rice productionAugust 20, 2010, Commodity Online

http://www.commodityonline.com/news/Climate-change-threatens-Asia-rice-production-31109-3-1.html

Rising temperatures during the past 25 years have already slashed the yield growth rate of rice by 10% to 20% in several areas

In Vietnam, for example, more than 50% of rice production is grown in the Mekong River delta, all of which would be affected by sea-level rises

Flooding caused by rising sea levels puts as much as 49 million acres of rice-growing area at risk of being submerged

References McMichael, A., & Haines, A. (1997). Global climate

change: the potential effects on health. British Medical Journal, 315(7111), 805.

Jonathan A Patz, Diarmid Campbell-Lendrum, Tracey Holloway, & Jonathan A Foley. (2005). Impact of regional climate change on human health. Nature, 438(7066), 310-7.  Retrieved August 21, 2010, from ProQuest Health and

Medical Complete. (Document ID: 936965231).http://www.ambiente.sp.gov.br/proclima/artigos_dissertacoes/

artigos_ingles/projectionsofafutureclimatechange.pdfwww.epa.gov/climatechange/science/futurecc.htmlwww.ucsusa.org › Global Warming