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Atmospheric weather veriables

Atmospheric weather veriables

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Atmospheric weather veriables

weather is the state of the atmosphere. Most weather occurs in the troposphere, or the lowest layer of the atmosphere. Weather is made up of multiple parameters, including air temperature, atmospheric (barometric) pressure, humidity, precipitation, solar radiation and wind. Each of these factors can be measured to define typical weather patterns and to determine the quality of local atmospheric conditions.

The environmental conditions produced by different weather parameters have an impact on the quality of the surrounding ecosystem. Weather elements form a chain reaction, as the impacts do not remain solely in the atmosphere. Temperature, pressure and humidity (moisture) can interact to form clouds. These clouds, in turn can reduce solar radiation for plants, or increase precipitation, which can runoff into a body of water. Consistently high temperatures can increase the heat transfer to local bodies of water in addition to heating the air. Likewise, a lack of precipitation affects not only weather conditions, but soil moisture and water levels due to evaporation. Wind speed and direction can be indicative of a front moving into the area, or it can create waves and encourage a stratified water column to mix.

Weather monitoring can establish a database of typical conditions. When one or more weather elements deviate from this standard, the information can be used to explain or predict weather events. Monitoring weather conditions is important not only as an environmental baseline, but to maintain quality working conditions, marine studies and recreational safety.


Elements Weather General, among others:

Solar Radiation Energy

Solar radiation is expressed in units of watts per meter squared (W / m2). Solar radiation is radiant energy from the fusion process or the incorporation of hydrogen nuclei in the sun into a hydrogen atom. This fusion process produces energy in the form of long-wave emission forwarded to the Earth’s atmosphere to the surface. This process is what causes the solar thermal energy can be felt in the atmosphere to the earth’s surface. Solar radiation is the most important factor that plays a role in weather formation processes in the Earth’s atmosphere because of the radiation is the sun “hot” is obtained for the “driving force” cycles in the atmosphere that cause weather changes from time to time. In meteorological observation synoptik (surface), solar radiation is observed by means solarimeter.

Air Temperature

The air temperature is the degree of ‘all hot-ness “of the air in a room or area restrictions. Unit air temperature is generally expressed in degrees Celsius or Kelvin in SI (International Units). The air temperature occurs because of the flow of heat energy from the sun through long wave radiation into air molecules in the atmosphere and other objects molecule on the surface of the earth. Physically each molecule’s ability to absorb and store solar radiation varies so different temperatures terbut molecules.

Air heating can occur through two heating process, namely the direct heating and indirect heating. a. Heating directly

Direct heating can occur through several processes as follows:

1) The process of absorption is the absorption of solar radiation elements, such as gamma rays, X-rays and ultra-violet. Elements that absorb solar radiation are oxygen, nitrogen, ozone, hydrogen, and dust.

2) The process of reflection is solar heating of the air but reflected back into space by drops of water (H2O), clouds, and other particles in the atmosphere.

3) The process of diffusion of sunlight experienced diffusion of light in the form of short-wave blue and violet scattered in all directions. This process causes the blue sky. b. Indirect heating indirect heating can occur in the following ways:

1) Conduction is the provision of heat by the sun on the bottom of the air layer and then a layer of air that provide heat to the lining of the air above it.

2) Convection is the provision of heat by the movement of air vertically upward.

3) is the provision of heat advection by air motion horizontal (landscape).

4) Turbulence is the provision of heat by the air motion is irregular and swirling upward, but there are some of the heat is reflected back into the atmosphere.


Pressure physically defined as the force per unit area (F / A). Air pressure is the force exerted on the air molecules per unit area of ​​the column. The air pressure occurs due to air molecules in a column suffered heavy force due to gravity. Meanwhile, the air pressure changes occur due to differences in temperature on a column of air that causes differences in expansion of air so that the air pressure is different.

The units of measure the air pressure is millibars (mb) or hector-pascal (hPa).

1 mb = 1 Hpa = 3/4 mmHg (pressure mercury) or 1,013 mb = 76 cm Hg = 1 atmosphere

The air pressure is different at each point depends on the intensity or solar radiation, altitude, and latitude location somewhere. The higher the elevation of a point lower air pressure at that place. This happens because the air mass centered on areas that have a lower elevation due to the force of gravity so that the regions with higher elevations, the air mass in units of columns lighter than in lower elevation areas. Thus the air pressure will be lower in areas that have a higher elevation. At high latitudes, the air pressure in the area was strongly influenced by the air temperature due to the circulation of the sun’s apparent latitude of the earth. For example, in December in the southern hemisphere is dominated by pressure area is lower than in the northern hemisphere due to the apparent movement of the sun in December were in the vicinity of the 230LS and vice versa.

For standard air pressure based on the pressure at sea level (mean sea level pressure) in the amount of 1013.25 mb. The air pressure in meteorological observations, measured by a barometer aneroid or mercury barometer. Changes in air pressure over time affects the weather conditions change because it will lead to weather disturbances ranging from local scale to the global scale. Air pressure information is also very important in aviation activity.


The wind is generally defined as the movement of air masses due to the difference in air pressure in different places. In observation of Meteorology, wind velocity observed in substance and direction of the wind. Wind speed unit commonly used in meteorological observations are knots (Northicalmiles) and units of wind direction expressed in degrees.

The winds were observed in meteorology is the wind on the surface and winds at each vertical air layer. Surface wind is observed from a height of approximately 10 meters above the ground, assuming no obstacles (an obstacle) which is more than twice the height of the object. While the wind on the vertical air layer (upper air winds) was measured by the method of balloon pilots and is also widely used radio sounding (Rason) automatically.

The wind, in terms of meteorological scale can be divided into:

  1. Wind local scale. for example, onshore wind, sea breezes, foehn wind, wind valleys, mountain wind.
  2. Wind regional scale. for example monsoonal winds
  3. Wind a global scale. contohnhya Passat winds.
  4. Evaporation

Evaporation or evaporation is the event of changing water into water vapor. Evaporation is influenced by solar radiation, temperature, pressure and wind circumstances. In observation meteorlogi synoptik evaporation measured by evaporimeter in millimeters.

Relative Humidity (RH)

The relative humidity is the state that indicates the amount of water vapor contained in the air is saturated at the saturated vapor pressure.

Air humidity meteorological observations measured using psychrometer or hygrometer can also be used.

Conditions cloud

Clouds are formed due to the evaporation process on the surface of the earth. However, the cloud is not always develop in any area of a large evaporation. This is due to the influence of wind and currents subsidence in the area.

High clouds according dasarnnya divided into three, namely:

High clouds

Clouds are included in this category are clouds Cirrus, Cirrocumulus cloud, cloud Cirrustratus.

Cloud medium

Clouds are included in this category are Altostratus clouds, Altocumulus clouds and cloud Nimbustratus.

Low clouds

Clouds are included in this category are Cumulus clouds, Stratus clouds, clouds Stratocumulus and Cumulonimbus clouds.

Cloud according to its shape is divided into two, namely:

clouds Cumuloformis Clouds have lumpy shape ssehingga allows this cloud has a base height of the low and high peaks towering.

Cloud stratoformis

Shaped cloud sheet or layer uniform and relatively homogeneous. These clouds do not have high cloud tops because the top layer of clouds is difficult to know the height due to terturup layer below.

In convective clouds like cumulonimbus cloud dynamics process occurs in the form of cloud updraft flow dab downdraft that often endanger aviation activity, because that’s observations about the existence of this type of cloud is indispensable.

The content of the cloud of water vapor in a state dominated saturated (RH> 95%) except in high clouds and cumulonimbus cloud tops (grounded) dominated by ice crystals.

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