Global Environmental

Problems and

Global Efforts

ByN.S.Srinidhi, Asst. Professor, Vidya Jyothi Engineering College, RR - Telangana

GREEN HOUSE EFFECT

55% contributor to Global

Warming & 500 yrs life span

18% contributor to

Global Warming

(GW) and 7-10 yrs

life span

6% contributor

and 140-190 yrs

life span

1000 yrs life span

CFC’S24% Contributor &

life span of 110 yrs

GLOBAL WARMING Presences of GHE, avg. global

temperature is 15°C.

In absences of them it would be -18°C.

Therefore GHE, contributes 33°C temperature rise.

Two Important GHG’s are Water Vapour & CO2.

BCoz of excess GHG’s, scientist worry about incraese in avg temp. more than 15°C.

Causes due to Deforestration, Anthropogenic activities like fossil fuel burning.

This leads to Sea Level Rise.

SEA LEVEL RISE

In the last century 15-20 cm rise in se level has been witnessed.

IPCC projected rise in between 18 and 59cms.

Reasons:

1)Thermal Expansion2)Melting of Ice

End of 21st Century, rise is expected to be between 0.56 and 2m.

Melting of Greenlands & West Antarctica – 6m rise.

Causes:

Flooding of Coastal areas like Bangladesh, Mumbai, Lakshadweep

Disturb Spawning grounds.

Disturb Coastal Fisheries.

Flooding agriculture lands & low land.

Increases Soil Erosion

Increases Salinity of aquifers & Estuaries.

Inundate large areas of Wetlands.

CLIMATE CHANGE1. Climate is the average weather of an area.

2. The Intergovernmental panel of Climate Change (IPCC) – 1990 & 1992 published the best available evidence about past climate change, GHE and Global Warming during the geological times.

3. Anthropogenic activities – Upset Hydrological Cycle, Results in flood and Drought, causes sea level rise, changes in agriculture productivity, famines, death of humans & livestock.

4. The global changes in temperature will not be uniform everywhere and will fluctuate in different regions.

5. Poles experience 2 to 3 times more warming than the global average, while warming in the tropics may be only 50 to 100% on an average.

Earth’s Temperature will rise in between 1.5°C to 5.5°C by 2050.

Impact on Human Environment

1. Global Temperature Increase:

2. Rise in Sea Level:Expanding of water due to

increase in temperature.

•Melting of Polar Ice Caps.

•Increase in Global Sea

Level by 0.2-1.5 metres

over the next 50-100 years.

•One meter rise will

inundate Sydney, Bangkok,

Cairo etc, Agricultural

Lands of Bangladesh, India,

China will effect rice

production.

•Lives of many people living

near these cities.

3. Effects on Human

Health:

Spread of Diseases like

Filariasis, Elephantiasis,

Malaria etc.

As the Vectors spreading

these diseases will be

increase in no. due to

stagnation of water and

high temperature to

survive(Mosquitoes, Snails

Etc).

Increase in Respiratory and

Skin Diseases due to high

temp. & Humidity.

4. Effect on

Agriculture:

•Soil Moisture will

decrease & evapo-

transpiration will

increase – affecting

wheat and maize

production.

•Increase in pest no.

due to high temp. &

Humidity.

•To cope up this pest,

heat and drought

resistant varieties to be

developed.

OZONE LAYER DEPLETION

Ozone Formation

Atmospheric Ozone measured using Dobson

Spectrophotometer and expressed in Dobson

Units(DU).

Temperate Latitudes = 350 DU

Tropics = 250 DU

Sub- Polars = 450 DU

Ozone Hole:

An undeniable problem in Antarctica

Researcher Joseph Farman had been collecting

atmospheric data at Halley Bay, Antarctica since

1957. Every year he sent a team of research

assistants to measure ozone levels and

concentrations of trace gases like CFCs.

In 1982, his ozone reading showed a dramatic dip

— around 40%. Rather than being alarmed, he was

skeptical of the data and thought it must be an

instrument malfunction.

Ozone Hole over the Anatartica

OZONE DEPLETING SUBSTANCES1. CFC’s2. Halon3. Carbon Tetrachloride(CCl4), Methyl Chloroform(CH3CCl3)4. Hydrobromofluorocarbons (HBFC’s)5. Hydrochlorofluorocarbons(HCFC’s)6. Methyl Bromide(CH3Br)7. Bromochloromethane(CH2BrCl)

Effects of Ozone Depletion1. Mutation in the DNA – Hereditary Problems.2. Skin Cancer.3. UV absorbed by lens and Cornea – Cataract.4. Melanin in skin destroyed by the UV.5. Decrease in Phytoplankton Population – Later impacting the ecosystem.6. Yield of crops like corn, rice, soyabean, cotton etc are decreased.7. Degradation of Paints, Plastics and other polymer material will result in economic loss due to UV rays.

Deforestation

Facts: Forest Cover in Total World in 1900 was 7000 Million

Hectares, but in 1975 – 2980 Million Hectares and in 2000 – 2300 Million Hectares.

Due to global efforts in 2010 it increased to 4033 Million Hectares.

In next 60 years about 90% of the tropical forests will be destroyed.

India’s Forest cover is 21.02%.(2009 Forest Report)

Major Causes of Deforestation Shifting Cultivation

Fuel Requirement

Raw Material for Industrial Use

Developmental Projects.

Growing Food Needs.

Over Grazing

Forest Fires.

Consequences

Extinction of Species due to habitat loss.

Hydrological Cycle effected thereby effecting rainfall.

Soil Erosion and loss of soil fertility.

Landslides in hilly areas.

Moe Carbon is added into the atmosphere, thereby enhancing Global Warming.

Desertification

Productive Potential of Arid & Semi-Arid lands falls by 10% or more.Moderate Desertification – 10-25% drop in productivity.Severe – 25 – 50%Very Severe – more than 50%

Consequences:Loss of VegetationGround water depletionSalinization and severe soil erosion

Causes of Desertification

Natural Phenomena – Climate Change

Anthropogenic Factors

1. Deforestation

2. Over Grazing

3. Mining and Quarrying.

Thank You