Fundamentals of Agrometeorology and
Climate Change
Course Outline
1. Introduction
2. Solar Radiation, Air Temperature, Humidity, Wind,
Precipitation, Soil Moisture and Temperature,
Evapotranspiration, Statistical Calculation of Variables
3. Weather and Climate Forecast
4. Climate Classification
5. Climate Extrimities: Drought and Flood
6. Agro-meteorological Models
7. AutomaticWeather Station
8. Climate Change and Its science
Introduction of Agrometeorology
Agrometeorology = Agriculture + meteorology
Meteorology is generally defined as a branch of physics that
deals with the physical process in the atmosphere that
produces weather and climate.
The physical process are influenced by solar radiation,
temperature, humidity, wind movement, atmospheric
pressure, precipitation and soil moisture.
Meteorology is concerned with the study of the characteristic
and behavior of the atmosphere.
It explains and analyses the changes of individual weather
elements such as air pressure, temperature and humidity that
are brought about due to the effect of insolation on the
earth’s surface.
Agrometeorology
❖ Agricultural meteorology, or agrometeorology, addresses topics
that often require an understanding of biological, physical, and social
sciences.
❖ It studies processes that occur from the soil depths where the
deepest plant roots grow to the atmospheric levels where seeds,
spores, pollen, and insects may be found.
❖ Agricultural meteorologists collect and interpret weather and
climate data needed to understand the interactions between
vegetation and animals and their atmospheric environments.
❖ Agricultural meteorologists also quantify, evaluate and provide
information on the impact and consequences of climate variability
and change on agriculture.
Definition
❖ Agrometeorology is a branch of meteorology that examines the
effects and impacts of weather and climate on crops, rangeland,
livestock, and various agricultural operations.
❖ It is a science investigating the meteorological, climatologic and
hydrologic conditions, which are significant for agriculture owing
to their interaction with the objects and processes of agricultural
production.
❖ In nutshell, it is a science dealing with climatic conditions,
which is directly related to agriculture.
❖ Therefore, agrometeorology is the study and application of
relationships between meteorology and agriculture, involving
problems such as timing the planting of crops.
Objectives of Agrometeorology
Overall Objective: To discover and define effects of weather and climate on
agriculture (plants and animals) for practical use.
Specific Objectives
➢ To increase quantity and quality of agriculture production through selection
of crops and crop varieties of best fit to prevailing condition of weather and
climate
➢ To increase or enhance the efficiency of agriculture operation through
efficiency of input use
➢ To help appropriate use of land
➢ To avoid the irreversible abuse of the land resources
➢ To protect the crop and livestock from adverse climatic risk by an incidence
and extent of pest and diseases
➢ To study about soil erosion from wind and water incidence and effect of
drought, frequency and extent of frost
➢ To provide guidelines for short and long term planning
Scope of Agrometeorology
❖ Climatic factors alone affect the yield of crops to an extent of about 40 %.
❖ In Nepal, the success of agriculture depends mainly on monsoon rains.
❖ Agrometeorology is mainly concerned with microclimatology in which
the influence of the shallow layer of atmosphere immediately above the
surface is studied.
❖ Successful crop production depends not only upon the total seasonal
rainfall but also on the proper distribution.
❖ Therefore, weather and climate is a resource and considered as basic input
or resources in agricultural planning, every plant process related with growth
development and yield of a crop is affected by weather.
❖ Similarly, every farm operation such as ploughing, harrowing, land
preparation, weeding, irrigation, manuring, spraying and dusting, harvesting,
threshing, storage and transport of farm produce are affected by weather.
1.Weather Monitoring
➢ In 1988 AD, Department of Hydrology and Meteorology is established in
Nepal
➢ 282 stations (including 22 agrometeorological stations) located in
different parts of the country to measure weather conditions
➢ Temperature, humidity, rainfall, direction and velocity of wind and rate of
evaporation are monitored
➢ World Meteorological Organization (WMO), the international agency
responsible for worldwide climatic data, is located in Geneva, Switzerland
2. Agrometeorological Forecasting
➢ Forecasting of weather condition and trend
➢ Forecasting of insects and disease to decide transplanting of crops,
spraying of insecticides and pesticides to control disease and harvesting
the crops
3. Crop zonation and Crop Planning
➢ Environmental condition can be regionalized based on latitude, altitude,
day length etc.
➢ Nepal is divided into five crop zones- tropical, sub- tropical, temperate,
sub alpine and alpine
4. Weather Crop Relationship
➢ The relationship between weather and selection of crop according to the
prevailing weather condition
5. Climatic Control
➢ Cannot control climate in huge scale
➢ Micro modification is possible
➢ Achieved by the use of greenhouse
➢ Important in the research to maintain environment of certain place
➢ Helps in agro climatic classification and crop weather modeling
History of Agrometeorology
❖ Superstition served to interpret atmospheric mysteries such as rain, wind
and lightening.
❖ In the early civilization, Gods were often assigned to the climatic elements.
❖ Nepalese still hold ceremonial worships/dances to Gods to produce rains
at times of drought.
❖ The word “Meteorology has been borrowed from Aristotle’s “Meteorologica”
dated about 350 BC.
❖ In 1593, Galileo constructed a thermometer; and in 1643, his student
Torricelli discovered the principles of mercurial Barometer.
❖ By 1800, dependable weather observations were made in Europe and USA.
An International Meteorological Organization had been established in 1878.
❖The World Meteorological Organization (WMO) took its present form in
1951, head quarters in Geneva, Switzerland.
❖ In case of Nepal, formal observation and making the data base system is
done by Department of Hydrology and Meteorology (DHM).
Department of Hydrology and Meteorology
❖ Government of Nepal started hydrological and meteorological activities in
an organized way in 1962.
❖ The activities were initiated as a section under the Department of
Electricity.
❖ Section was subsequently transferred to the Department of Irrigation and
was ultimately upgraded to this Department in 1988.
❖ Department with headquarters in Kathmandu has three basin offices:
Karnali Basin Office in Nepalgunj, Narayani Basin Office in Narayanghat and
Kosi Basin Office in Biratnagar.
❖Has four regional offices namely Office of Hydrology and Meteorology in
Dharan, Pokhara, Bhairahawa and Kohalpur.
❖DHM has a mandate from Government of Nepal to monitor all the
hydrological and meteorological activities in Nepal.
❖The scope of work includes the monitoring of river hydrology, climate,
agro-meteorology, sediment, air quality, water quality, limnology (study of
the biological, chemical, and physical features of lakes and other bodies of
fresh water), snow hydrology, glaciology, and wind and solar energy.
❖General and aviation weather forecasts are the regular services provided
by DHM.
❖ As a member of the World Meteorological Organization (WMO), DHM
contributes to the global exchange of meteorological data on a regular basis.
❖ DHM actively participates in the programs of relevant international
organizations, such as, the UNESCO's International Hydrological Program
(IHP) and WMO's Operational Hydrology Program (OHP).
❖ The department is also a focal point for Intergovernmental Panel on
Climate Change (IPCC) and for the meteorological activities of SAARC.
❖ International Civil Aviation Organization (ICAO) has recognized DHM as
an authority to provide meteorological services for international flights.
❖ DHM maintains nation-wide networks of 177 precipitation stations, 68
climatic stations, 22 agro-meteorological stations, 9 synoptic stations and 6
Aero-synoptic stations, and 51 hydrological stations,.
❖Data are made available to users through published reports, bulletins, and
computer media outputs such as hard copies or diskettes.
Application of Agrometeorology
• Characterization of agricultural climate
• Crop planning for stability in production
• Crop management
e.g 1) Weeding harrowing, mulching etc are undertaken during dry spells
forecasted.
2) Fertilizer application is advisable when rainfall is not heavy wind speed
is<30 km/hr and soil moisture is between 30 to 80%
3) Spraying/dusting is undertaken when there is no rainfall, soil moisture is
90% and wind speed is < 25km/hr.
•Crop Monitoring
• Crop modeling and yield –climate relationship
• Research in crop –climate relationship
• Climate extremities
• Climate as a tool to diagnose soil moisture stress
• Livestock and Fishery production
