Agro-meteorology Flashcards
Meteorology word derived from?
Greek word:
Meteoro + Logy =
Above the Earth’s Surface + study
Physical State of the atmosphere at a given place at a given time (relatively short-term)
Weather
What is the seat of photochemical reaction?
Stratosphere
In which layer of atmosphere are earth’s clouds present?
Trophosphere
The lowermost and topmost atmospheric layer of earth?
Trophosphere
Exosphere
What are the parameters or the external factors affecting crop production?
LAP-TV
Latitude, Altitude, Precipitation,
Topography, Vegetation,
Precipitation in arid and semi arid areas?
Arid: <500mm
Semi arid: 750-1000mm (max in India)
Precipitation in sub-arid & humid regions?
sub-arid: 750-1000mm
Humid: >1000mm
Dimensions in scale of weather
Height
Horizontal Scale
Time
Categories of Scales of Climate as per IMD Pune
Macro
- Planetary and Synoptic
Meso
Micro
Climatic conditions that last for a few minutes and occur in less than 1km area horizontally and 10m vertically in the atmosphere
Micro-Climate
Eg: dew, industial smoke, small eddy currents, etc.
Scales of Micro, Meso and Macro climatic condition as per IMD
Micro, Meso, Synoptic, Planetary
<1km, 1-100km, 100-1000km, 1000+ km
<10m, 1-10km, 1-10km, 10 km
few mins, 1 day, few days, Large no. of days
Scales of Micro, Meso and Macro climatic condition as per other authors
Micro, Meso, Synoptic, Planetary
<100m, 1-100km, 200-500km,2k-5k km
200m, 1-10km, 10km, 10 km
6-12 min, 1-10 hrs, 100 hrs, 200-400hrs
Examples of Meso Climatic conditons
Thunderstorms (convective clouds), tornados, Dust storms, fog, land & sea breeze, etc.
Examples of Synoptic Planetary conditions?
Depressions, Cyclonic storms, troughs & ridges
Examples Planetary climatic conditions?
Global circulation, ITCZ, Monsoon troughs, etc
Permanent change in weather phenomenon and temporary change is weather phenomenon from normal
Climate change
Climate variability
Different people/organisations that made Climate Classifications?
- Thorne Thwaite: PHMDSA
- Troll: ASSH
- ICAR: SSA
What is the Thorne Thwaite Classification of Climate based on?
Moisture index
Measured through Potential Evapo-Transpiration (PET)
What is the Thorne Thwaite Classification
PHMDSA
Per Humid: 100+
Humid: 100-20
Moist sub-humid: 20-0
Dry sub-humid: 0 to -33.3
Semi Arid: -33.3 to -66.7
Arid: -66.7 to -100
What does the Troll Criteria depend on?
No. of Humid Months
What is the Troll classification?
ASSH
Arid: <2 months of rain - 17% India
Semi-Arid Dry: 2-4.5 months - 57%
Semi-Arid Wet: 4.5-7 months - 12%
Humid: >7 months of rain - 1.10%
What does the ICAR’s criteria of Climate classification depend on?
Moisture Deficit Index
What is the ICAR Classification of Climate?
SSA
Sub-Humid: 0-33.3
Semi-Arid -33.3 to -66.6
Arid: >-66.6
How many metrological sub-divisions are there in India?
36
Most of our average annual rainfall is during?
Monsoon: 70% of the 125cm
Average of Max and Min temperature of day minus the base temperature of the crop
Degree Day of the Crop
(Tmax - Tmin) / 2 - T base
What is:
1. used to guide agricultural operations and planting land use
2. Forecast crop havest dates, yield & quality
3. Forecast labour req
4. done before Introducing new crops
5. Predicting the liklihood of successful growth
Growing Degree Day
Precipitation of liquid water particles either in the form of drops of diameter greater than 0.5mm or smaller widely scattered drops
Rain
Uniform precipitation of fine drops, less than 0.5mm in diameter
Drizzle
Fine drops of less than 0.5 mm that completely evaporate before touching ground?
Mist
Precipitation of white and opaque grains of ice (solid water in branched hexagonal crystals)
Snow
A mixture of rain & snow, small pellets of transparent ice 5mm or less in diameter. Happens when rain falling to earth passes through a layer of cold air and freezes
Sleet
In High altitute in winter
Small pieces of ice of diameter 5-50+ mm. Dreaded & destructive storms that are more frequent in the tropics, March - May in India
Hail
Lines connection areas of equal amount of precipitation
Isohytes
Lines connecting areas of same temperature
Lines connecting areas of same atmospheric pressure
Isotherm
Isobar
Average value of 30 years of a particular weather element continuing for a week, month, or years
Climatic normal
What depends on the climatic normal of a place?
crop distribution, production and productivity
When isobars are eliptical than circular, the system is called?
Ridge or wedge
A low pressure region that brings winds the velocity of 40-120 km/hr mostly during the summer. Those in Bay of Bengal and Arabian Sea brings heavy rainfall and a change in existing weather
Storm
A combination of heat and moisture with speeds exceeding 120km/hr originating from water vapour rising from the warm sea/ocean and lasts longer than a storm
Hurricane in North Atlantic and eastern North Pacific.
Typhoons in Western North Pacific
Willy Willies in Australia
Cyclones in the Indian Ocean
Storms by cumulonimbus clouds, accompanied by lightning & thunder
Thunderstorms
Violently rotating column of air attended by funnel/tubular shaped cloud extending downwards from the base of a cumulonimbus
Most violent storms of troposphere
Occur during spring or summer, mostly
Tornado
General Water phenomenon that is controlled by meteorological factor that occurs in night at well and is dependent on temperature and humidity
Evaporation
Water phenomenon controlled by both meteorological and plant factors
Transpiration
What is the classification of a Hot month, Cold month and warm month?
> 20 degrees
15-20 degrees
0-10 degrees
Photosynthetic activities take place in what range of solar radiation?
Visible Light Range
0.39-0.76 meu
What is the value of solar constant?
2 cal/cm2/min
Solar Radiation that reflects back into the atmosphere after striking an object or air in earth, & is not transformed into heat. % of reflected radiation to the incident radiation
Albedo
Albedo of clouds?
55%
Shade loving plants and Sun loving plants are known as?
Sciophytes: Betel vine, Buck Wheat
Hetrophytes: Maize, Sorghum, cereals (rice, wheat)
The plant injury where due to high temperature of 50-60 degrees where plant cells get killed
Thermal Death Point
Injury caused on the barks of stem by high temperature during day time and low during night time
Sun Clad
Stem at ground level scorches, due to high soil temperature causing death of plant by destroying conductive tissue. Eg: Cotton in sandy soil
Stem Girdle
Plants of hot climate, exposed to low temp and are killed or severely injured or development of chloratic condition (yellowing). Eg: Sorghum & Maize during winter when night temp is below 20 degree
Chilling Injury
In plants of temperate region when exposed to very low temperatures, water in cells freezes into ice, protoplasm is dehydrated leading death. Eg: Frost damage of potato, tea, etc
Freezing Injury
Plant injury by lifting up of plants, along with
Heaving
What are the methods of classification of drought?
2 methods of classification
AS-MHA (AS in MaHA)
Conditions of Low Atmospheric Humidity, high wind velocity, high temp, where plants lose most of their moisture by transpiration
Atmospheric Drought
2 types of Soil Drought are?
Physical & Physiological
Actual shortage of water due to limited or non-availability of water from various sources
Physical Water Drought
Phenomenon where water is available but plants can’t absorb them due to physiological reasons like excessive salts or imbalanced pH, etc.
Physiological Soil Droughts
Phenomenon when seasonal rainfall is less than 75% of its long term average over a wide area
Meteorological Drought
Phenomenon where waterbodies start drying up, causing depletion of surface water and drying up of inland water bodies and a decrease in water level
Hydrological drought
Meterological drought leads to hydrological drought
Phenomenon where Inadequate soil moisture and rainfall impact crop growth, leading leading to extreme crop stress, yield loss and wilting of plants
Agricultural Drought
3 types of weather forecasting?
- Short Range: Now Casting, Very Short Range
- Medium Range
- Long Range
Weather forecast range upto 72 hours is called? It forecasts?
Short Range
For Rainfall distribution, rainfall rate (heavy/low), thunderstorms and heat or cold waves
Short range forecasting is used by?
Farmers, Mariners and different Agencies
Weather forcast for the next 0-2 hours
Now casting
Weather forecast for the next 1-12 hours?
Very Short Range Forecast
Weather forecast for the next 3-10 days? it is for predicting?
Medium Range
For predicting Rainfall occurance and temperature
National Centre for Medium Range Weather (NCMRF) Forecasting is located in?
Noida, UP
Noida needs medium rain
Weather forecast beyond 10 days, up to a month or a season is? it is for?
Long Range Forecast
For Indian Monsoon and Expected Rain Amount
Who uses Long Range Weather Forecats?
Planners
A scheme by IMD, State Agricultural Universities and ICAR, which renders medium range weather forecast based Agromet Advisory Services to the farmers at the district level
Gramin Krishi Mausam Sewa Scheme
8 weather parameters considered in GKMS Scheme?
Grameen Krishi Mausam Seva
- Rainfall
- Max Temp
- Min Temp
- Morning & Evening Relative Humidity
- Wind Speed
- Wind Direction
- Cloud Cover
Who prepares the Agromet Advisory in GKMS Scheme and when is it relelased?
ICAR-CRIDA with IMD
Every Friday
An enormous volume of meteorological data is being collected from all over the world continuously round the clock through various telecommunication channels
The observations are plotted on maps in standard weather codes for assimilation. This kind of map is known as?
Synoptic Charts
What does a Full white circle in Synaptic Charts represents?
Clear sky
What does a Full black circle in Synaptic Charts represents?
Overcast
What does a semi colon in Synaptic Charts represents?
Drizzle
What does a Double Line in Synaptic Charts represents?
Mist
What does a triple line in Synaptic Charts represents?
Fog
Detailed agricultural information collected by IMD, condensed and presented in pictorial form
Crop Weather Calendar
How many parts does a crop weather calendar have?
3 parts:
Bottom, Middle, Top
What does the bottom part of a Crop Weather Calendar show?
Phenological stages of crop and the months
Which part of a crop weather calendar shows the weather conditions required for active crop growth
Middle part
Divided into Rainfall, Min/Max Temp, Sundhine Hours, Pan Evaporation
Which part of a Crop Weather Calendar gives information regarding weather abnormalities (precautionary measures)
The Top Part
Divided into Dry spell length, High wind, Heavy rainfall, Cloudy weather
Representation of crop through mathematical equations explaining the crop’s interaction with both above ground and below ground environment
Crop Modelling
Model where relationship between the yield or yield components with weather expressed, measured using Statistical techniques
Statistical Model of Crop Modelling
Crop model that explains not only the relationship between weather parameters and yield, but also influencing dependent variables
Mechanistic model
Crop model that estimate the exact value of the yield or dependable variable
Deterministic Model
A crop model where a probability element is attached to each output. These models define the yield or state of dependent variable at a given rate
Stochastic Model
Crop model where time is included as a variable. Both dependent and independent variables have values which remain constant over a given period of time
Dynamic Models
A crop modeling system where time is not included as a variable. The dependent and independent variables having value remain constant over a period of time
Static model
Computer crop models that are a mathematical representation of a real world system. Used to estimate agricultural production as a function of weather and soil conditions
Simulation models
A crop model that defines the behaviour of the system in a simple manner. Has one or more mathematical model
Descriptive model
Crop model that consist of quantitative description of the mechanism and process that causes the behaviour of the system
Explanatory model
Sowing of what is influenced by NE monsoon in southern india
Sowing of RABI
Oct to Dec
