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Angin adalah udara yang bergerak. Untuk menggerakkan udara dibutuhkan kekuatan. Faktor awal yang mengembangkan angin adalah karena perbedaan suhu horizontal di troposfer. Massa udara (dan udara dengan suhu dan sifat kelembaban yang berbeda pada skala yang lebih kecil) akan memiliki kepadatan yang berbeda dan perbedaan kerapatan ini menyebabkan perbedaan tekanan antara daerah yang ditemui massa udara atau udara yang berskala lebih kecil. Gaya yang yang berpengaruh untuk menggerakkan udara adalah Gaya Gradien Tekanan. Ada faktor-faktor lain yang memengaruhi kecepatan dan arah angin (Coriolis, gesekan, sentrifugal, dll.), tetapi Gaya Gradien Tekanan penyebab utamanya. Karena perbedaan suhu terjadi pada semua skala (global, sinoptik, mesoscale, dan lebih kecil), pola angin juga ada pada semua skala ini. Di bawah ini adalah daftar istilah angin yang mencakup jenis angin dan terminologi penting untuk angin dalam meteorologi.
Advection-The horizontal motion of air (parallel to sea level)Anemometer-An instrument used to measure wind speedBacking wind-A wind that shifts in a counterclockwise direction with height. For example, an east wind at 850 mb and a north wind at 700 mb would be a backing wind. Also can be a wind shift at the surface or a particular pressure level in which over time the wind shifts in a counterclockwise direction at a point location.Calm-A wind speed of less than 3 knots.Convection-A vertical motion of air. The transfer of energy by mixing a fluid.
Coriolis is the deflection a parcel of air takes relative to the Earth's surface due to Earth's rotation.
The city tends to be warmer than the surrounding countryside. During period of clear weather with weak synoptic wind a breeze will blow from the countryside toward the city. The city air is warmer and thus rises and is replaced by countryside air.
Rotating in the same sense as low pressure. A cyclonic flow is counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.
Air that sinks with the terrain as it moves toward lower elevations. Downsloping air warms adiabatically and decreases in relative humidity.
Eddy-A rotation or spin-off that is embedded within a fluid. Convection will have eddies at the edges of where air with different temperature and moisture properties is mixing.Gale Wind-A wind speed ranging from 39 to 54 mph.Geostrophic Wind-A wind that is balanced by the Pressure Gradient Force and Coriolis. To remain in geostrophic balance the wind needs to occur in the middle or high latitudes (since Coriolis is strong enough there) and needs to flow at a constant speed and direction (to prevent ageostrophic accelerations and centrifugal accelerations).Gust Front-A boundary separating downdraft air from a thunderstorm and the surrounding environmental air. Air tends to be cool and gusty behind the gust front.Isotach-A line of equal wind speed.Jet Stream-The Jet Stream is a global upper tropospheric wind belt that separates mid-latitude air from polar air.Katabatic Wind-Air that flows under the influence of gravity from higher toward lower elevations. A air is initially very cold thus it has a high density and is thus negatively buoyant.Land Breeze-A wind caused by the differential heating between land and water. During the night the land cools more than the water. This promotes higher pressure on the land surface and lower pressure on the water surface. Since air flows from higher toward lower pressure the wind flow is toward the ocean.Meridional flow-Meridional flow is a wind flow through highly amplified troughs and ridges.
Extremely cold air in high elevations that blows into the western Mediterranean basin from the French Alps. Even though the air warms by adiabatic compression, it starts out so cold that it still ends up being a cold wind.
A wind that blows from the mountains at night due to differential cooling. The mountains slopes cool more at night than the valley. The cooling air becomes more dense and then flows toward the valley.
The dominate wind direction at a location for a particular season.
Santa Ana- A warm and dry wind in southern California. Low pressure to the south of the area and high pressure to the north of the area set up a dry and adiabatically compressed wind that comes out of the higher elevations.
A sea breeze is a wind caused by the differential heating between land and water. During the day the land heats more than the water. This promotes lower pressure on the land surface and higher pressure on the water surface. Since air flows from higher toward lower pressure the wind flow is from the ocean.
Trade Wind-An easterly band of wind in the tropics. The easterlies are equatorward from the subtropical highs.Upsloping Wind-Air that rises with the terrain as it moves toward higher elevations. Upsloping air cools adiabatically and increases in relative humidity.Valley Breeze-A wind that blows from the valley toward the higher elevations during the day. The mountain slopes warm more than the valley during the day due to more direct exposure to the sun. This produces lower pressure along the mountain slopes and thus the flow is from the higher pressure air in the valley toward the lower pressure air on the mountain slope.
A wind that shifts in a clockwise direction with height. For example, a south wind at 850 mb and a west wind at 700 mb would be a veering wind. Also can be a wind shift at the surface or a particular pressure level in which over time the wind shifts in a clockwise direction at a point location.
The movement of air. Wind when measured is usually measured as the horizontal component of the wind speed (parallel to Earth's surface).
A device used to measure wind direction.
A zonal flow is a large scale wind flow that is fairly parallel to the lines of latitude
Demikianlah terminologi angin dalam meteorologi, semoga bermanfaat.