It is the science of the atmosphere and its phenomenon
(which we call weather). The reason for daily interest in weather is that it is
new every morning. It is never stable for long but always in the state of
becoming something new. Meteorology combines physics and geography.
The meteorologist is seriously involved in the science
of the atmosphere from which he gets enough information to forecast the
possible condition of the weather. The study of atmosphere by the meteorologist
is confirmed to the lower atmosphere that is responsible for weather.
What is Atmosphere?:- It is refers to all the gaseous contained in water
and soil in equilibrium with certain envelope.
Atmospheric resources
The most important atmospheric resource by man are
water, solar energy and wind but equally important to man are:
- Water
- Solar energy
- Wind
- Heat
- Atmospheric gases
WATER VAPOUR
The water vapor is contributed to
the air by evaporation from water surfaces soil and living tissues and combustion.
It is found in a very little amount in the air of the instants and Polar
Regions of the would and in much more volume in the wind and humid tropics.
SOLAR ENERGY
Solar
Energy is the main energy input in the earth system.
The atmospheric energy sources can
be reduced in quality through atmospheric pollution by man in the following
ways:-
- Introduction
of dust particles from land surface e.g during hammattan period in Nigeria and
content factories etc.
- Introduction of soil, land and gases
- Surface combine peroxide and
hydrocarbons from molar vehicles.
WEATHER AND CLIMATE
Weather:- is simply the atmospheric condition of a particular place
of a particular time it is temporal. It helps in determining the climate.
Climate:- is the average condition of atmosphere over along
period of about 35yrs. Climate takes longer time for it to occur usually in
35yrs climate depends on position on “globe”
DIFFERENCES BETWEEN WEATHER AND CLIMATE
WEATHER CLIMATE
1. Weather is daily or hourly Climate
is average
Of atmospheric condition or sum total
condition
of a place.
Of an area.
2. It
observed within a short it is observed within a long period
Period of time of time
3. It is
highly variable is constant and can be peneralize
period of time.
4. It is
considered in a shot is considered over a large place
like village or town area.
5. it is
a basic of study planet It is a fundamental for the study of
climatology
WHEATHER STATIONS
Weather stations usually measure pressure, temperature,
daily maximum and minimum temperature, wind speeds, wind directions, humidity,
cloud cover, solar radiation and precipitation. A good weather station must
meet quite stringent requirement. Weather station is required to be in an open
field, so that local building and obstruction do not disturb their measurements
of wind speed and directions. They must be treat shade and must meet other
important criteria.
TYPES OF WEATHER STATION
1. Synoptic
station:- They are professional and full time observers. They takes data in
hourly bases and their data is used for forecasting.
2. Agricultural
Station:- They have part-time observers. They takes data twice in a day their
data has to do with Agricultural practice
3. Climatologically
Station:- They also have part-time observers. They take data that has to deal
on weather element.
4. Rainfall
Station:- They take data twice in a day per day. They take data that concern
only rain dropper day.
METEOROLOGICAL
INSTRUMENTS
Instruments that are found in weather station include
1. Thermometer
-------- temperature
2. Barometer
(mercury and Aneroid)-------- pin pressure
3. Hydrometer-------------
humidity
4. Wind
vane--------- wind direction
5. Anemometers------------
wind speed
6. Ceilometers-----------
cloud height
7. Rain
gauge and snow gauge--------- rain fall
Stevenson’s
screen:- it’s a double layered. It
has wooden and metal pan. It’s double layered in order to prevent direct sun
ray that will influence the readings. It’s raised 1-2m above ground level on a
still. It’s heure like in nature or Venetian blind. Its painted white to inactivate
sunlight inside the Stevenson screen is minimal and maximum thermometer. It’s levies
like in nature so as to take the atmospheric pressure
Maximum thermometer:- A mercury is glass thermometer. Its calibrated to
take the highest temperature reached in a day its calibrated to 0.5oC
deference. It does not reduce when the temperature shorts dropping. It stats reading
around once the sun is out.
Minimum Thermometer:- its alcohol in glass thermometer. It’s calibrated to
take minimum temperature reached in a particular day it stats reading around
1am – 3am. The graduation is 0.5oC.
DIFFERENCE BETWEEN MAXIMUM AND MINIMUM
THERMOMETER
Maximum Thermometer Minimum
Thermometer
- It uses mercury It uses Alcohol
- It takes the highest It takes the minimum temperature
temperature reached in reached in a day
a day
- It starts reading once It starts reading round
1am-3am in
the instrument is 1am
– 3am in the morning.
resettled as long the
sun is up.
Dry
bulb thermometer:- it uses mercury it takes the temperature of the air flowing
into the state. It’s calibration is 0.5oC
The factors that affect the dry bulb
thermometer are:-
- The
wind flowing into the state, how moist and warm that the air is.
- Cloud
coverage, Rainfall, Humidity.
Maximum and dry bulb works in hand to hand when the
temperature states dropping, the dry bulb also states dropping. The dry bulb
does not take the heat intensity of the state. It records the temperature of
wind flowing into the state.
Difference between maximum and dry bulb is that
maximum thermometer tells you the maximum temperature reached a day while the
dry bulb tells the temperature at a particular time.
Wet bulb thermometer:- A mercury in glass thermometer containing a wick that
is inserted in a water. It’s design to tell how moist the wind flowing into that
particular geographical area.
During
dry season the reading of wet bulb thermometer is high.
The difference of dry and wet bulb
is used to determine the relative humidity of a geographical area. The
calibration is 0.5oC.
Functions of Stevenson screen:-
- It serves as shelter to the
meteorological instrument.
- To prevent sum radiation panted white
to deflect radiation
WEATHER SATELLITES
A weather satellite is a type of satellites that is
primarily used to monitor the weather and climate of the earth. The advantage
of the weather satellite is that it sees more than clouds end cloud systems,
city lights, fires, effects of pollutions, sand and dust storms, snow cover,
the mapping, energy flows etc.
Types of meteorological satellites: The two basic types of meteorological satellites are
geo stationary and polar orbiting satellites.
1. Geostationary Weather Satellites-: The position of the satellite in the orbit makes it
remain stationary with respect to the rotating with and this can recorder
transmits images of the entire atmosphere below continuously with their
visible-light.
2. Polar Orbiting weather Satellites-: These circle the earth at typical altitude of 85km.
polar satellites are in sum-synchronous orbit, which they are able to observe any
place on Earth and will view every thing twice each day with the same general
lighting conditions due to the near-constant local solar time.
Precipitation-: The rain fall intensity, duration and distribution,
determine the effect the precipitation with have on agricultural production. If
the rainfall intensity is high, the consequence will be soil erosion as a result
of accumulation of excess water in the soil surface because the rate of
rainfall is higher than the infiltration capacity of the soil. On the other
hand, if rainfall is low, the result will be drought. The consequence of
drought is low agricultural production.
The Rainguage-: A meteorological Instrument used in recording
rainfall. It’s mounted in an open place where there will be no obstruction to
rainfall. Inside the rainguage is a metallic funnel. At the it has a ring like
shape. The essence is to prevent splashing water from entering inside the
rainguage. Inside the rainguage is a
metallic bucket. It’s known as emergency bucket. It’s used incase the bucket
that collect water gets filled during heavy rainfall to prevent loss of water.
Wind vane-: it’s used in measuring the wind. The wind vane consist
of a long metal that has it cardinal point. In between the cardinal point is a
blade and nobe. When jacking reading, we consider the nobe not the blade. The
wind coming to Ebonyi is from Southwest. The wind vane is sited at the true
north of the area.
Measuring Cylinder-: it is used in taking measurement of rainfall in a day
it’s calibrated 0-5oc differences. The s.i unit of measuring
rainfall is intimate.
Temperature-: temperature is not a much problem in agricultural
production in Nigeria. This is due to that the variation in temperature is
still within the ranges that required in crop production.
Relative humidity-:It has a significant impact on agricultural production
in Nigeria. This is simply due to low relative humidity in which crops and
evaporation, respectively.
Wind-: This causes the destruction of many economic trees and
crops such as palm trees, maize, okoro and oranges are usually destroyed by
heavy wind.
Hygrometer-: hygrometers are
instrument used for measuring humidity. A simple as a of hydrometer and consist
of two thermometer one of which is a dry bulb and the other a wet bulb
thermometer.