WEATHER FORECASTING
Type of weather forecast
|
|
Types of forecast
|
Validity period
|
Predictions
|
Uses
|
|
1
|
Short range
|
Up to 72 hours
|
Rainfall distribution, heavy
rainfall, heat and cold wave conditions, thunder storms etc.
|
Scheduling of irrigation
Adjusting of time of agricultural
operations
Protection of plants from frost
|
|
2
|
Medium range
|
Beyond 3 days and upto 10 days.
|
Occurrence of rainfall,
Temperature.
|
Useful to determine sowing time
Useful to determine depth of sowing
Planning of irrigation
Decision on harvesting
Decision on time of spraying to get
higher efficiency
Management of labour and equipment
|
|
3
|
Long range
|
Beyond 10 days upto a month and a
season.
|
This forecasting is provided for
Indian monsoon rainfall. The out looks are usually expressed in the form of
expected deviation from normal condition.
|
To decide on soil moisture management
to decide on irrigation scheduling
decision on selection of crops
decision to manage irrigation with
limited water supply
decide on cropping pattern and
to determine crop yield
|
CLIMATE
CHANGE
The earths atmosphere has never been free of change ( in
its composition, temperature, self-cleaning ability). Due to change in atmosphere the world is
warming, climatic zones are shifting; glaciers are melting and sea level is
rising. We anticipate these changes to accelerate over the next few years to
come.
Greenhouse
effect: The theory of "greenhouse effects" was conceived by the
French Mathematician J.B. Fourler over a century ago. It was supported by Tyndall's studies on the
absorption of heat by gases.
Increased human activities increase carbon dioxide,
methane, nitous oxide, chloro flurorocarbons (CFC) etc., which lead to increase
in temperature and sea level rise. These
gases which are in traces cause environmental parturbations ( distrubances)
such as green house effect ( global warming), stratospheric ozone depletion ,
acid deposition, smog and corrosion.
Environmental
Perturbations Responsible gases
1. Green house effect Co2,CH4(Methane,
N2, CFCS, Ozone
2. Ozone depletion in the
stratosphere Chloro-fluoro
carbons (CFCS)
3. Acid deposition SO2,
NO, NO2, S, O3
4. Smog corrosion SO2
AGRICULTURAL
SEASONS OF INDIA
Season is a period in a year comprising few months during
which the prevailing climate does not very
much. Growing season for a crop is more
important for its yield and other management practices to be followed.
Indian
Meteorological Department has divided the year into four seasons.
i. Summer : March- May
ii. Monsoon : June- September
iii. Post Monsoon : October- November
iv. Winter : December -
February
The monsoon season is designated as Kharif, whereas the
post monsoon and winter seasons are together designated as "Rabi"
throughout India.
Based on temperature ranges three distinct crop season
have been identified in India.
i.
Hot weather ( Mid February-Mid June)
ii.
Kharif or
rainy season ( Mid June-Mid October)
iii.
Rabi ( Mid October to Mid February)
In Southern
states ( Tamil Nadu, Andhara Pradesh and Karnataka) there is slight
variation in the season based on
rainfall duration as
1.
Winter -
January and February
2.
Summer -
March to May
3.
Rainy season -
a. South West monsoon - June to September
b. North East
monsoon - October- December
Based on the criteria, monthly precipitation and temperature,
the growing season is broadly divided as follows:-
i. Hot month -
if the average temperature is above 20oC
ii. Cold month -
if the mean temperature is between 0-10oC
iii. Warm month -
if the mean temperature is between 15-20oC
Comments
Post a Comment