acid rain is one of the most studied consequence of air pollution which causes rain water and soil pollution. Along with acid rain , red rain has become a major concern in recent years which causes threat in local people heart and mind. This presentation contains a detailed knowledge about acid rain and red rain.

1. ACID RAIN

2. Rain with elevated levels of hydrogen ion concentration
(pH < 5.6) is referred to as acid rain
According to classical concept:
Acid rain is formed when oxides of sulphur and nitrogen is
mixed with water vapors ,forming sulphuric acid and nitric
acid.
According to modern concept:
It is formed when sulphur dioxides and nitrogen oxides, as
gases or fine particles in the atmosphere, combine with
water vapor and precipitate as sulphuric acid or nitric acid
in rain, snow, or fog
WHAT IS ACID RAIN?

3. 3NO2 (g) + H2O (l)  2HNO3 (aq) + NO (g)
HNO3 (aq)  H + (aq) + NO3 - (aq)
SO2 (g) + O2 (g)  SO3 (g)
SO3 (g) + H2O (l)  H2SO4 (aq)

4. Causes
 Emission from volcanoes
 Industrial factories, power generating plants and vehicles
 Fuel burning
 Automobiles
FORMS OF ACID RAIN
a) wet deposition b) dry deposition

5. Effects
 Lowers the pH of water bodies , leading to death
of aquatic life
 It makes trees vulnerable to disease, extreme
weather, and insects by destroying their leaves,
damaging the bark and arresting their growth
 Decreases soil pH , which ultimately damage or
reverses soil biological and chemical activities

6.  Acid rain on buildings, especially those constructed
with limestone, react with the minerals and corrode
them away. This leaves the building weak and
susceptible to decay
 Intensified levels of acid depositions in dry form in the
air can cause lung and heart problems such as
bronchitis and asthma
 corrodes metals like steel, bronze, copper, and iron.

7. Canada
 Acid rain is a problem in Canada
 Water and soil systems lack natural alkalinity such as
lime base
 Cannot neutralize acid
 Canada consists of susceptible hard rock such as
granite
 Do not have the capacity to effectively neutralize acid
rain
AFFECTED AREAS

8. EURASIA AND U.S
 Industrial acid rain is a substantial problem in China,
Eastern Europe and Russia
 Acid rain from power plants in the Midwest United
States has also harmed the forests of upstate New
York and New England.

9. INDIA
 India, acid rain is not frequently observed due to tropical
climatic condition and alkaline dust particle which
neutralize it.
 According to a survey done by IITM,pune, due to
increasing pollution some of the Indian states(delhi, UP,
Maharastra, MP, Tamil Nadu ) are at high risk of acid rain in
future.
 Taj mahal is Affected by the acid rain over two decades due
to heavy industrialization in the places around agra and
Mathura.

10.  Reduce amount of sulphur dioxide and oxides of
nitrogen released into the atmosphere
 Use less energy (hence less fuel burnt) Use cleaner
fuels
 Remove oxides of sulphur and oxides of nitrogen before
releasing
 Flue gas desulphurization
 Catalytic Converters
Preventive measures

11.  Removes sulphur dioxide from flue gas (waste gases)
 Consists of a wet scrubber and a reaction tower equipped
with a fan that extracts hot smoky stack gases from a
power plant into the tower
 Lime or limestone (calcium carbonate) in slurry form is
injected into the tower to mix with the stack gases and
reacts with the sulphur dioxide present
 Produces pH-neutral calcium sulphate that is physically
removed from the scrubber
 Sulphates can be used for industrial purposes

13.  Taj mahal is effected by the pollutant over two
decades due to heavy industrialization in the places
around agra and Mathura.
 Major contributor of pollutant is Mathura oil refinery
 As per metrological studies the wind direction is
usually move in the direction where Taj is situated
 Thus White taj starts to go yellow
TAJ MAHAL

15.  Precious and semi precious stones of the Taj weathered
away due to acid rain
 The sulfuric and nitric acids in the rain causes the calcite to
dissolve and makes gypsum form
 Gypsum causes the area of affected stone to turn black
and when the gypsum falls off it reveals crumbling stone
 To protect Taj Mahal, a government of India institute
called NEERI targets at clearing the air in 'Taj Trapezium'.
Taj Trapezium refers to an area that includes towns of
Agra, Mathura, Bharatpur and Firozabad. As a result of this
plan, over 2000 industries situated inside the trapezium
had transferred. Still the current situation is critical
because of nearby leather industry.

16.  Observed in the year 25july-23 September 2001 in the
districts of Kottayam and Idukki, Kerala
 This rain is red due to colored air borne spores from
locally proliferic terrestrial algae belonging to the
genes Trentepholia.
 It falls typically over small area and last for few
minutes
RED RAIN

18.  Recently this rain was observed in Norilsk, Siberia
in Russia. Metal processing giant Norcnickel revealed
the rain was caused by a clean up operation on the
factory floor of the local Nadezhdinsky processing
plant.
 The blood rain was caused when vast amounts of red
iron oxide residue, more commonly known as rust,
was scraped off the factory’s floor.