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Meteorology (気象学)

Mount Usu / Sarobetsu post-mined peatland
From left: Crater basin in 1986 and 2006. Cottongrass / Daylily

[ climatology | disaster ]

Weather forecasting
Biological meteorology (生物気象学)

Agricultural meteorology (農業気象学)

Maritime meteorology, etc.

an eclispe seen at
Sapporo on October 8 2014


[ ultraviolet ]

Solar radiation or insolation (日射)

energy input → changing with latitudes and seasons

Energy balance

Rn = H + IE + G + (Ain - Aout) + ΔSt + ΔP

St = Z1z2[(ΣiρiciTi/∂t]dz + Z1z2[(ρalq)/∂t]dz

H: sensible heat flux

heats air
eddy transport ≫ thermal conduction

IE: latent heat flux

eddy transport

G: ground heat flux

heats ground, melts snow and ice
thermal conduction

Atmosphere (大気)

Beaufort scale of wind force (ビューフォート風力階級)
an empirical measure showing wind speed (at 10 m above the sea surface) to observed conditions

Ex. Beaufort number. description: wind speed, kt/m·s-1 (wave height, m): sea conditions; land conditions

  1. Calm (静穏): < 1/0.5 (0);
    sea like a mirror
    smoke rises vertically
  2. Light air (至軽風): 1-3/0.5-1.5 (0-0.3):
    ripples with appearance of scales are formed, without foam crests
    direction shown by smoke drift but not by wind vanes
  3. Light breeze (軽風): 4-6/1.6-3.3 (0.3-0.6)
    small wavelets still short but more pronounced; crests have a glassy appearance but do not break
    wind felt on face; leaves rustle; wind vane moved by wind
  4. Gentle breeze (軟風): 7-10/3.4-5.5 (0.6-1.2)
    large wavelets; crests begin to break; foam of glassy appearance; perhaps scattered white horses
    leaves and small twigs in constant motion; light flags extended
  5. Moderate breeze (和風): 11-16/5.5-7.9 (1-2)
    small waves becoming longer; fairly frequent white horses
    raises dust and loose paper; small branches moved
  6. Fresh breeze (疾風): 17-21/8-10.7 (2-3)
    moderate waves taking a more pronounced long form; many white horses are formed; chance of some spray
    small trees in leaf begin to sway; crested wavelets form on inland waters
  7. Strong breeze (雄風): 22-27/10.8-13.8 (3-4)
    large waves begin to form; the white foam crests are more extensive everywhere; probably some spray
    large branches in motion; whistling heard in telegraph wires; umbrellas used with difficulty
  8. High wind, moderate gale, near gale (強風): 28-33/13.9-17.1 (4-5.5)
    sea heaps up and white foam from breaking waves begins to be blown in streaks along the direction of the wind; spindrift begins to be seen
    whole trees in motion; inconvenience felt when walking against the wind
  9. Gale, fresh gale (疾強風): 34-40/17.2-20.7 (5.5-7.5)
    moderately high waves of greater length; edges of crests break into spindrift; foam is blown in well-marked streaks along the direction of the wind
    twigs break off trees; generally impedes progress
  10. Strong/severe gale (大強風): 41-47/20.8-24.4 (7-10)
    high waves; dense streaks of foam along the direction of the wind; sea begins to roll; spray affects visibility
    slight structural damage (chimney pots and slates removed)
  11. Storm, whole gale (暴風): 48-55/24.5-28.4 (9/12.5)
    very high waves with long overhanging crests; resulting foam in great patches is blown in dense white streaks along the direction of the wind; on the whole the surface of the sea takes on a white appearance; rolling of the sea becomes heavy; visibility affected
    seldom experienced inland; trees uprooted; considerable structural damage
  12. Violent storm (烈風): 56-63/28.5-32.6 (11.5-16)
    exceptionally high waves; small- and medium-sized ships might be for a long time lost to view behind the waves; sea is covered with long white patches of foam; everywhere the edges of the wave crests are blown into foam; visibility affected
    very rarely experienced; accompanied by widespread damage
  13. Hurricane force (颶風): ≥64/≥32.7 (≥14)
    the air is filled with foam and spray; sea is completely white with driving spray; visibility very seriously affected
*: wind speed codes are somehow different between regions or researches. The units (単位) are also different.
Wind direction (風向)
Fig. Compass rose (meteorological compass) wind
Fig. Connection of Beaufort force, Fujita scale and Mach number.

V = 1.87081.5 mpg = 0.836B1.5 m/s
V = 141(F + 2)1.5 mph = 6.30 (F + 2)1.5 m/s
V = (742 + 1.3t)M mph = (331 + 0.6t)M m/s

Cloud ()

Def. A visible mass of liquid droplets or frozen crystals made of water or various chemicals suspended in the atmosphere (→ aerosols) above the surface of a planetary body
Clouds Clouds
Clouds Clouds

Cloud classification

cirro-: curl of hair, high
alto-: mid
strato-: layer
nimbo-: rain, precipitation
cumulo-: heap

Aerosol (エアロゾル)

Natural aerosol = cloud, volcanic ash, (fire smoke - sometimes anthropogenic), etc. Anthropogenic aerosol = factory emission, veichle exhaust, etc.
ENSO → El niño, inducing severe wildfire (in southeastern Asia)
Aerosol optcal thickness (AOT) or depth (ADT)

Precipitation (降水)

Pan evaporation (計器蒸発量)
A measurement that combines or integrates the effects of several climatic elements, such as temperature, humidity, rain fall, drought dispersion, solar radiation and wind

Application: agriculture - to know how much water the crops need

Weather (天気)

the state of the atmosphere, describing for example the degree to which it is hot or cold, wet or dry, calm or stormy, clear or cloudy

AMeDAS (アメダス)

= Automated Meteorological Data Acquisition System (probably Japanglish)
Research sites [ database ]
Sarobetsu Mire: 45°06N, 141°42E, 7 m a.s.l.
Toyotomi (豊富): 45°06.1'N, 141°46.8E, 14 m (7 km far from the post-mined peatland)

temperature, precipitation, snowfall, snow depth, sunshine hour, wind speed, wind direction

Horonobe (幌延): 45°00.4'N, 141°51.1'E, 5 m (13 km)


Numakawa (沼川): 45°14.9'N, 141°51.1'E, 23 m (20 km)

temperature, precipitation, snowfall, snow depth, sunshine hour, wind speed, wind direction

Wakkanai (稚内): 45°24.9'N, 140°40.7'Ee, 2.8 m (> 30 km)

temperature, precipitation, snowfall, snow depth, sunshine hour, global solar radiation, wind speed, wind direction

Mount Usu: 42°30'N, 140°50'E, 727 m a.s.l.
Toya Spa (洞爺湖温泉): 42°39.9'N, 140°48.4E, 85 m

precipitation, snowfall, snow depth

Date (伊達): 42°28.5'N, 140°50.9'E, 3 m

temperature, precipitation, sunshine hour, wind speed, wind direction

Mount Koma: 42°03'N, 140°40'E, 1133 m a.s.l.
O-numa (大沼): 41°58.6'N, 140°42.9E, 165 m

precipitation, snowfall, snow depth

Mori (森): 42° 04.0'N, 140°35.3'E, 125 m

temperature, precipitation, snowfall, snow depth, sunshine hour, wind speed, wind direction

Forecast (天気予報)

the application of science and technology to predict the state of the atmosphere for a future time and a given location
settled weather (落ち着いた天気) ↔ hazardous or significant weather (悪天)