Glossary

absolute zero [11] 絶対0度:

the lowest theoretically possible temperature: –273.15°C or 0 K.

adaptation [139] 適応:

an approach to dealing with the changing climate by modifying our lifestyles.

adiabatic [60] 断熱(-的):

an adiabatic process involves no transfer of heat between a system and its surroundings.

advection fog [62] 放射霧:

fog generated by the transport of warm, moist air over a colder surface, which causes the air to cool below its dew point, and condensation to occur.

aerosols [45] エーロゾル:

small particles that are suspended in the atmosphere. Aerosols include dust, soot and sea salt.

African Easterly Jet [92] アフリカ東風ジェット:

a low-level jet stream that flows east to west off the coast of western Africa and plays a part in the formation of Atlantic hurricanes.

ageostrophic wind [71] 非地衡風:

the component of the wind that flows in a direction parallel to the pressure gradient (perpendicular to the isobars).

air frost [19]:

an air frost is said to occur if the air temperature falls below 0°C.

air mass [79] 気団:

a large volume of air having fairly uniform properties, such as temperature and humidity.

albedo [51] アルベド:

the fraction of incoming radiation that is reflected from a surface.

altocumulus [25] 高積雲 (十種雲型):

a mid-level cloud, usually made up of a sheet of many small cells or rolls of cloud.

altocumulus lenticularis [109]:

lens-shaped clouds that form downwind of hills and mountains.

altostratus [25] 高層雲 (十種雲型):

a mid-level cloud, consisting of a fairly uniform layer. Altostratus may be thick enough to obscure the Sun.

anabatic wind [111]:

an uphill flow of air on a mountainside. The warming of air on a mountainside causes the air to become less dense than its surroundings and flow uphill.

analysis [117] 「解析」:

a global snapshot of weather conditions that is used to initialise a forecast run.

anemometer [20] 風速計:

a term for any device that measures wind speed.

aneroid barometer [20] アネロイド気圧計:

a type of barometer that uses a partially evacuated metal capsule to measure changes in air pressure.

anomalous propagation [31]:

false returns on a radar image caused by refraction of the radar beam under a temperature inversion.

anticyclone [78] 高気圧:

an area of high pressure.

anticyclonic gloom [79]:

long periods of overcast weather associated with cloud trapped in an anticyclone.

anvil cloud [100]:

the vast shield of ice cloud that spreads out around the top of a cumulonimbus.

aphelion [66] 遠日点:

the point of the Earth’s orbit when it is furthest from the Sun.

Arctic air mass [80] 北極気団:

a mass of air that originated over the Arctic Ocean.

argon (Ar) [36] アルゴン:

an inert gas that makes up nearly 1% of the Earth’s atmosphere.

atmosphere [35] 大気、大気圏:

the narrow layer of air that enshrouds the Earth.

atmospheric window [52] 「大気の窓」:

a range of wavelengths in the electromagnetic spectrum (between 8 µm and 11 µm) in which thermal radiation is largely transmitted through the atmosphere.

attenuation [31] 減衰:

reduction of strength of a radar beam as it passes through heavy rain.

attribution [137] 因果関係の評価、「原因特定」、「要因分析」:

the linking of changes in global temperatures to various climate forcings.

Azores High [75] アゾレス高気圧:

the area of high pressure that is often found over the sub-tropical Atlantic.

backing [20]:

the wind is said to be backing if it is changing in an anticlockwise direction (for example, from northerly to westerly).

barograph [21] 自記気圧計:

a barometer that keeps track of air pressure over time, allowing trends in pressure to be determined.

barometer [20] 気圧計:

a term for any device that measures air pressure.

Beaufort scale [811] ビューフォート風力階級:

a scale of wind speed categories that runs from 0 (calm conditions) to 12 (hurricane conditions), developed by Francis Beaufort.

Bergeron–Findeisen process [48]:

a process by which ice crystals in a volume of supercooled liquid water droplets can rapidly grow at the expense of the liquid water.

black bodies [50] 黒体:

theoretical objects that emit electromagnetic radiation with maximum efficiency.

blocking anticyclone [82] ブロッキング高気圧:

an anticyclone that remains in location for long periods of time and disturbs the passage of mid-latitude depressions.

bomb [86] 「爆弾低気圧」:

a term used to describe any midlatitude depression whose central pressure falls by more than 24 hPa in 24 hours.

boundary conditions [121] 境界条件:

information about the weather conditions at the boundaries of a smaller-scale model that must be fed in from a larger-scale model to keep the regional model running.

boundary layer [40, 120] 境界層:

the lowest part of the troposphere where the flow is affected by interaction with the Earth’s surface.

butterfly effect [130]:

attributed to Edward Lorenz, an analogy used to describe the chaotic nature of the atmosphere: that the flap of a butterfly’s wings in one place could grow to initiate storms in another.

Buys Ballot’s law [70] 「ボイス・バロットの法則」:

this states that, if an observer backs the wind in the northern hemisphere, low pressure is to the observer’s left.

Campbell–Stokes sunshine recorder [22] キャンベル・ストークス型 日照計:

a device for measuring sunshine duration, consisting of a glass orb that focuses sunlight onto a strip of card.

cap cloud [110]:

a smooth cloud that forms on the top of a hill or mountain.

carbon dioxide (CO₂) [36] 二酸化炭素:

a greenhouse gas that exists in the atmosphere in small quantities, but is an important factor in global warming.

Celsius scale [9] セルシウス (摂氏) 温度目盛り:

a temperature scale first defined by Anders Celsius, which uses the freezing point of water (0°C) and the boiling point of water (100°C) as reference points.

Central England Temperature [16] 「中部イングランドの気温」:

a temperature record from stations in central England that stretches back to 1659 – the longest existing observational record.

chaotic [130] 「カオス的」:

a chaotic system follows a strict set of rules, but has so many degrees of freedom that the smallest change at one location within the system could have large impacts on the state of the system after a period of time.

cirrocumulus [25] 巻積雲 (十種雲型):

a high-level ice cloud made up of small, shadowless cells or ripples of cloud.

cirrostratus [25] 巻層雲 (十種雲型):

a high-level, thin and tenuous sheet of ice cloud that makes the sky look pale and can produce optical effects around the Sun.

cirrus [23] 巻雲 (十種雲型のひとつのことと、広い意味とがある):

high-level, wispy streaks of ice cloud.

climate [131] 気候:

the average weather conditions in a location over a long period of time.

climate feedback [136]:

any process that causes a change in the state of the atmosphere where the change then acts to either strengthen or weaken the process.

climate forcing [136]:

an impact that perturbs the balance of the climate system.

climate modelling [15]:

the act of using modified weather forecast models to predict conditions over much longer periods of time.

climatic observations [19] (下の記述はイギリス気象庁の観測の分類としての意味らしい):

a set of observations that are only made once a day.

cloud cover [13] 雲量:

the fraction of the sky that is obscured by cloud, usually quoted in eighths or oktas.

cloud head [85]:

a comma-shaped hook of cloud found in the centre of a severe midlatitude depression, usually associated with heavy rain.

clustering [123]:

the division of an ensemble forecast into groups of forecasts that show similar predictions of weather conditions.

coalescence [45] 併合:

the growth of raindrops by individual drops colliding and merging with other drops.

cold conveyor belt [85]:

one of the three air streams that maintains a mid-latitude depression, consisting of a stream of cold air that flows into the centre of the depression from ahead of the warm front.

cold-core anticyclone [79]:

a type of anticyclone driven by surface cooling, which leads to increased air density near the surface.

cold desert [112]:

the sort of desert found in the Arctic and Antarctic, which usually have icy surfaces.

cold front [80] 寒冷前線:

a boundary where a mass of cold air undercuts a mass of warmer air, leading to ascent and cloud development.

condensation [9] (気象学用語としては) 凝結、(物理・化学用語としては) 凝縮:

the conversion of water vapour into liquid water.

conduction [62] (熱)伝導:

the transfer of heat through a solid object by molecular vibrations.

continuity [69] 連続。流体力学用語としては質量保存をさす。:

the principle that, in a flow, fluid cannot be created or destroyed.

convection [59] 対流:

the transfer of heat within a fluid by motion of the fluid, which leads to contrasts in properties within the fluid becoming smoothed out.

convective clouds [61]: 対流性の雲

a generic term for clouds that form when parcels of warm, moist air rise vertically in unstable conditions and saturate. Convective clouds include cumulus and cumulonimbus.

convective overshoot [100]:

a dome found on the top of a cumulonimbus above the updraught, where the ascending air is pushing against the tropopause.

convergence [69] 収束:

this occurs at a point in a fluid when there is more horizontal flow into the point than there is leaving it.

Coriolis force [70] コリオリの力:

the effective force on a mass of air that is caused by the rotation of the Earth.

cumulonimbus [23] 積乱雲 (十種雲型):

tall, deep clouds consisting of liquid water near their bases and vast shields of ice at the top. These clouds bring showers of rain, hail, thunder and lightning.

cumulus [23] 積雲 (十種雲型のひとつのことと、広い意味とがある):

low-level clouds that have a flat base and extend upwards in a dome.

cumulus congestus [23, 98] 雄大積雲:

tall cumulus clouds that may be deep enough to bring some rain.

cumulus humilis [21, 94]:

small, flat cumulus clouds.

cyclogenesis [80] 低気圧の発生・発達:

the formation and strengthening of mid-latitude depressions.

data assimilation [119] データ同化:

the technique of mathematically combining weather forecast model output with observations such that the resulting state of the atmosphere contains no unrealistic artefacts.

dendrochronology [132] 年輪年代学 (dendroclimatology は 年輪気候学):

the analysis of tree rings; used to infer past climate conditions.

density [37] 密度:

the mass of a substance per unit volume, usually expressed in kg/m³.

depression [78] 低気圧 (そのうち弱いものをさすことが多い):

an area of low pressure.

deterministic forecasting [123] 決定論的予報:

a deterministic weather forecast uses a single model run that gives a single prediction of how the weather may evolve.

development site [82]:

a location where conditions are favourable for the development of mid-latitude depressions.

dew [62] 露:

liquid water that condenses on the surface when air adjacent to the surface is cooled to its dewpoint temperature.

dewpoint temperature [44, 62] 露点温度:

the temperature to which air must be cooled to cause it to saturate, assuming no changes to its pressure and its specific humidity.

diffuse radiation [52] 散乱日射:

light from the Sun that has reached the Earth’s surface having been scattered at least once by the atmosphere or its contents.

diffusion [45] 拡散:

the tendency of water vapour to flow from an area of higher concentration to an area of lower concentration.

direct radiation [52] 直達日射:

light from the Sun that has reached the Earth’s surface without having been scattered.

discretisation [120] 離散化:

the mapping of a continuous field of data onto a grid at fixed points.

dispersion [55] 分散:

the spreading out of light into its different wavelengths.

divergence [68] 発散:

this occurs at a point in a fluid when there is more horizontal flow leaving the point than there is arriving at it.

domain [121] 領域:

the area over which a weather forecast model runs.

Doppler radar [32] ドップラーレーダー:

a type of radar that transmits pairs of pulses to allow the movement of areas of rainfall to be determined.

downdraught [101] (アメリカつづり downdraft) 下降流:

the descending column of air at the heart of a convective storm system.

dry adiabatic lapse rate [60] 乾燥断熱減率:

the rate at which the temperature of a parcel of air will fall per unit height if it rises adiabatically and the air does not saturate.

dry-bulb thermometer [18] 乾球温度計:

a standard thermometer with its bulb exposed to the air, used to measure air temperature.

dry conveyor belt [85]:

one of the three air streams that maintains a mid-latitude depression, consisting of a flow of dry air into a mid-latitude depression behind the cold front.

dry intrusion [85]:

a cloudless band of drier air in a mid-latitude depression associated with the dry conveyor belt.

dust devil [112]:

a small vortex extending upwards from the ground, visible when it picks up dust.

electromagnetic radiation [10, 50] 電磁波の放射:

all radiation that is caused by oscillations of electric and magnetic fields. In meteorology, important types of electromagnetic radiation are visible light, ultraviolet and infrared.

El Niño [95] エルニーニョ:

a warming of the sea surface of the eastern Pacific Ocean, which has far-reaching impacts on world weather.

emissivity [51] 射出率 (「放射率」という訳語を見るが、さけたほうがよいと思う。):

the efficiency at which a surface emits radiation with respect to a black body at the same temperature.

Enhanced Fujita Scale [105] 「改良藤田スケール」 (たつまきの強さの尺度):

the scale on which the severity of tornadoes is quantified.

ensemble forecasting [122] アンサンブル予報:

the act of running a number of forecasts with slightly different initial conditions to give an idea of forecast uncertainty.

environmental lapse rate [60. 98] 環境の気温減率 (この「環境」は上下に動く空気塊にとっての動かない環境):

the background rate of change of temperature of the atmosphere with height.

equilibrium [51] 平衡、つりあい:

a system in equilibrium is in perfect balance: for example, it gains the same amount of energy as it loses.

evaporation [43] 蒸発:

the conversion of liquid water into water vapour.

eye [94] 台風の目:

the small patch of clear sky found in the centre of a tropical cyclone caused by local subsidence of the air.

eye wall [94] :

the band of storm cloud surrounding the eye of a tropical cyclone.

Fahrenheit scale [9] ファーレンハイト (華氏) 温度目盛り:

a temperature scale, proposed by Gabriel Fahrenheit, that originally used the freezing point of water (32°F) and human body temperature (96°F) as reference points, although it now takes its reference points from the Celsius scale.

fair-weather cumulus [98] 晴天積雲:

another term for cumulus humilis – small cumulus clouds.

Ferrel cell [74]:

part of the three-cell model of atmospheric circulation. The Ferrel cell is a weak circulation that spans the gap between the Hadley and polar cells and rotates in the opposite direction, with rising air in the midlatitudes and descent over the sub-tropics.

fluvial flooding [110] (川から水があふれる洪水):

a type of flooding where excess rainfall causes the ground to become saturated and water to run straight off the surface.

fog [61] 霧:

cloud that forms at the surface and reduces visibility to less than 1 km.

Föhn effect [111] フェーン効果 (日本語では「フェーン現象」のほうがよくきかれるが):

an effect that creates warm, dry winds in the lee of mountain ranges.

forked lightning [102]:

lightning that passes from cloud to ground, allowing its branching structure to be seen.

freezing fog [62]:

fog, consisting of supercooled liquid droplets that instantly freeze onto any cold surface.

freezing rain [62] 雨氷:

raindrops that are composed of supercooled water, which freeze onto cold surfaces leading to the build up of crusts of ice.

frontal wave [80]:

a wave in the polar front which marks the first stage of development of a mid-latitude depression.

frost [62] 霜:

ice crystals that freeze on the surface when air adjacent to the surface is cooled to its dewpoint temperature and the temperature is cold enough.

funnel cloud [105] ろうと[漏斗]雲:

a funnel-shaped protrusion from the base of a cloud. Funnel clouds that extend to the ground become tornadoes.

future climate scenarios [137] 将来気候シナリオ:

trends of how greenhouse gas emissions may continue into the future, devised for the IPCC Assessment reports.

Galileo thermometer [8] ガリレオ式温度計:

a type of thermometer consisting of a number of glass spheres suspended in a fluid within a closed glass container.

geoengineering [139] 「ジオエンジニアリング」、「気候工学」。意図的気候改変をさすことが多い。:

a number of proposed projects to tackle increasing global temperatures by modifying the planet.

geostationary satellite [32] 静止衛星:

a satellite in geostationary orbit travels directly above the Equator and takes exactly one day to travel around the Earth once. This means that it always remains in the same position in the sky.

geostrophic wind [71] 地衡風:

the component of the wind that flows in a direction perpendicular to the pressure gradient (parallel to the isobars).

global model [121] 全球モデル:

a weather forecast model that generates forecasts on a grid that covers the whole world.

grass minimum temperature [19]:

the lowest temperature reached overnight, measured using a thermometer at grass level.

graupel [48] あられ:

small, soft ice particles a few millimetres in diameter.

gravity [38] 重力:

the downward force felt on Earth that is due to the Earth’s mass.

greenhouse gases [52, 134] 温室効果気体:

a number of gases present in the atmosphere, including carbon dioxide, water vapour and methane, which absorb thermal radiation and warm the Earth.

Greenwich Mean Time [16] グリニッジ標準時:

the time in London (excluding daylight saving time), used to determine UTC.

ground clutter [31]:

false returns on a radar image caused by reflection of the radar beam off the ground and other immovable objects.

ground frost [19]:

a ground frost is said to occur if the grass minimum temperature falls below 0°C.

guidance [124]: 「ガイダンス」

the first step in issuing a forecast. The guidance is an overview of how the weather is expected to develop and is compiled by senior forecasters.

gust front [101]:

the boundary of the plume of cold air from the downdraught of a cumulonimbus that spreads out when it reaches the ground.

haboob [112]:

a wall of dust, raised by an advancing gust front ahead of a storm.

Hadley cells [72]:

part of the three-cell model of atmospheric circulation. The Hadley cells are convective circulations that span the tropics, with their ascending branches over the Equator and their descending branches over the sub-tropics.

halo [56] ハロ:

a circle of light refracted off ice crystals that can sometimes be seen around the Sun or Moon.

heat capacity [106] 熱容量:

a measure of how much heat energy is required to warm a surface by a certain temperature difference.

hectopascal (hPa) [20] ヘクトパスカル:

a standard unit of pressure, equivalent to 100 pascals or 1 millibar. Standard atmospheric pressure is 1,013.25 hPa.

heterogeneous nucleation [45] 不均質核形成:

the condensation of liquid droplets or ice crystals with the assistance of an aerosol particle.

heterosphere [41]:

the part of the atmosphere where gases are no longer well mixed. This extends upwards from about 100 km above the surface.

hole-punch cloud [48]:

a hole that forms in a layer of supercooled liquid water cloud when glaciation is initiated, often by the passage of an aircraft through the layer.

Holocene [133] 完新世:

the most recent epoch of geological time, defined as the last 12,000 years.

homogeneous nucleation [44] 均質核形成:

the spontaneous condensation of liquid droplets or ice crystals in pristine, clean air.

homosphere [41]:

the part of the atmosphere where the gases are well mixed. This extends from the surface up to a height of about 100 km.

hot desert [112]:

the sort of desert found in the tropics and sub-tropics that has a sandy or rocky surface.

humidity [19] 湿度:

a measure of the amount of water vapour held in the atmosphere.

hurricane [92] ハリケーン:

a name for intense tropical cyclones that form in the Atlantic.

hydrological cycle [43] 水循環:

the continuous passage of water between the ocean, the atmosphere and the land.

hydrostatic balance [68] 静水圧のつりあい:

for the atmosphere to be in hydrostatic balance, the upward pressure gradient force must be equal to the weight of the atmosphere above.

hygrometer [19] 湿度計:

a term for any device that measures humidity.

ice age [133] 「氷河時代」:

a prolonged period of colder climatic conditions, usually associated with the advance of the polar ice caps.

infrared radiation [49] 赤外線(の放射):

electromagnetic radiation with wavelengths between about 750 nm and 1 mm. Thermal radiation consists of infrared radiation.

initial conditions [16] 初期条件:

the global snapshot of information about the state of the atmosphere that is used to initialise a forecast run.

Intergovernmental Panel on Climate Change (IPCC) [135] 気候変動に関する政府間パネル:

a WMO panel that summarises current research into climate change into regular Assessment Reports.

interpolation [118]: 内挿、補間

the act of inferring the weather conditions at a point between observations by assuming that the conditions vary smoothly.

Intertropical Convergence Zone (ITCZ) [68] 熱帯収束帯:

the zone of convergence where the Hadley cells in each hemisphere meet, generating a band of ascent marked by a patchy band of convective cloud around the tropics.

ionisation [41] 電離:

the charging of atmospheric molecules.

ionosphere [41] 電離層:

a layer of charged particles found in the lower thermosphere. The ionosphere is an important part of the Earth’s electric circuit.

isobars [4] 等圧線:

lines on a weather map that connect places of constant atmospheric pressure.

jet stream [75] 「ジェット気流」:

a stream of very fast-moving winds. The polar front jet stream runs in the upper troposphere in association with the polar front and is a major factor in the growth and dissipation of mid-latitude depressions.

katabatic wind [111] 「カタバ風」、斜面下降風:

a downhill flow of air on a mountainside. The cooling of air on a mountainside causes the air to become more dense than its surroundings and flow downhill.

Kelvin scale [11] ケルビン温度目盛り:

a scale of temperature that increases upwards from absolute zero, using the same temperature increment as the Celsius scale.

khamsin [113]:

a warm wind that blows across the Mediterranean from Egypt to the eastern Mediterranean countries.

knot [20] ノット (海里毎時):

a unit of speed, often used in meteorological observations, equivalent to one nautical mile per hour.

lake effect snow [108]:

snowfall that occurs when cold winds pass over lakes and seas, causing heating and an outbreak of convection.

laminar flow [40] 層流:

in a fluid, laminar flow is characterised by organised motion in layers, with no eddies or vortices.

land breeze [107] 陸風:

a light wind that blows from the land to the sea on a clear night. It is caused by the different properties of the land and sea surfaces.

La Niña [96] ラニーニャ:

a cooling of the sea surface of the eastern Pacific Ocean, which has far-reaching impacts on world weather.

leader stroke [102]:

the first stage of a lightning strike, which creates a path of ionised air.

leste, leveche [113]:

warm winds that blows across the Mediterranean from Morocco to the Iberian peninsula.

level of neutral buoyancy [60] 浮力中立高度 (日本語表現は一定しないようだ):

the level at which a rising plume of air is no longer less buoyant that the surrounding air, hence it can rise no further.

lidar [31] ライダー:

a system of cloud detection that is similar to radar, but uses light pulses instead of radio.

lifting condensation level [60] 持ち上げ凝結高度:

the level at which air in a rising plume of air begins to condense, appearing as the level of the cloud base.

Little Ice Age [66] 小氷期:

a period of lower global mean temperature that ran from the sixteenth century to the nineteenth century.

low-Earth orbit [32] 「地球低軌道」:

an alternative term for a polar orbit.

Madden–Julian Oscillation [90]:

a fluctuation in pressure that travels eastward around the tropics and alternately enhances and suppresses convection in the Intertropical Convergence Zone.

mammatus [101] 乳房雲:

lumpy undulations found on the base of a cumulonimbus.

mass mixing ratio [44] 質量混合比:

a method of quantifying humidity in terms of mass of water vapour per unit mass of dry air.

Maunder minimum [66] マウンダー極小期:

a period of low solar activity between about 1650 and 1700.

maximum thermometer [18] 最高温度計:

a thermometer designed to measure the maximum temperature reached over a period of time.

mean-sea-level pressure [20] 海面気圧:

the equivalent air pressure that would be measured at a weather station if it were situated at mean sea level.

melting layer or freezing layer [46] 融解層、凝結層:

the level in the atmosphere where the air temperature is 0°C and hence falling ice particles start to melt to liquid water.

mercury barometer [8] 水銀気圧計:

a type of barometer that measures pressure by the height of a column of mercury.

mesocyclone [104] メソ低気圧:

a storm system where the updraught and downdraught spiral around one another.

mesoscale [106] 中小規模、メソスケール:

mesoscale weather systems are typically of size a hundred kilometres.

mesosphere [40] 中間圏:

the layer of the atmosphere above the stratosphere, marked by decreasing temperature with height.

meteogram [124]:

a graph showing how various aspects of the weather are likely to evolve at a given point with time.

methane (CH₄) [36] メタン:

a greenhouse gas that exists in the atmosphere in very small quantities. It is also a major component of natural gas.

mid-latitude depression [69] 温帯低気圧 (そのうち弱いものをさすことが多い):

a structured low-pressure system that forms in the midlatitudes, normally with rain aligned along bands called fronts.

mid-latitudes [74] 中緯度:

the part of the Earth outside the Hadley circulation and containing the polar front, typically defined by latitudes between about 30° and 60°.

millibar (mb) [20] ミリバール:

a standard unit of pressure, equivalent to the hectopascal.

minimum thermometer [18] 最低温度計:

a thermometer designed to measure the minimum temperature reached over a period of time.

mitigation [139] 被害軽減、地球温暖化の文脈では「緩和策」:

an approach to dealing with the changing climate by taking action to combat it – for example, by reducing greenhouse gas emissions.

monsoon [90] モンスーン、季節風:

the reversal of wind direction in the tropics that separates wet seasons and dry seasons. The word ‘monsoon’ is also sometimes applied to the heavy rain associated with the wet season.

Moore’s Law [15] 「ムーアの法則」:

the recent trend in computing whereby the processing power of computers has been doubling every two years.

multi-cell storm [102]:

a convective system that consists of a number of cumulonimbus cells. These can persist for much longer than a single-cell storm.

negative feedback [136] 負のフィードバック:

if a change in temperature affects a property of the atmosphere such that it reduces the temperature change, a negative feedback process is said to occur.

negative lightning [102] (負電荷の雷放電):

a negative lightning strike occurs when the base of the cloud adopts a negative charge. Most lightning strikes are of this type.

nimbostratus [23] 乱層雲 (十種雲型):

a thick, low-level sheet of cloud that brings periods of persistent rain.

nimbus [23] 雨雲[あまぐも] (十種雲型ではない):

an obsolete term for a raincloud; one of Luke Howard’s original cloud types.

nitrogen (N₂) [36] 窒素:

a chemically inactive gas that makes up about 78% of the Earth’s atmosphere.

noctilucent cloud [40] 夜光雲:

thin ice clouds that form over the poles in the mesosphere.

North Atlantic Oscillation index [78] 北大西洋振動指数:

an index that quantifies the position of the North Atlantic storm track, based on the strength of the north–south pressure gradient across the North Atlantic.

Norwegian model [13] 「ノルウェーモデル」 (この「モデル」は概念モデル):

a model describing the development and life cycle of mid-latitude depressions, developed in the 1920s by a group of Norwegian scientists including Jakob Bjerknes.

nowcasting [126] ナウキャスト、短時間予報:

the prediction of the weather for a few hours ahead by looking at radar and satellite imagery.

numerical weather prediction [116] 数値天気予報:

the technique of forecasting the weather using physical equations to project the state of the atmosphere at a future point in time.

oblate [46] 扁平な:

an oblate sphere is wider than it is tall.

occluded front [80] 閉塞前線:

when a cold front catches up with a warm front, it lifts it up off the surface creating an occluded front or an occlusion.

occlusion [80] 閉塞:

the process that creates an occluded front.

okta [23] (八分の一):

the standard unit of cloud cover, where one okta is one eighth of the sky.

orographic enhancement [109] 地形による強化:

the intensification of rainfall caused by forced ascent over hills and mountains.

orography [109] 「山」～「地形」:

a general terms for hills and mountains.

oxygen (O₂) [36] 酸素:

a reactive gas that makes up about 21% of the Earth’s atmosphere.

ozone (O₃) [34] オゾン:

a gas that exists in the atmosphere in small quantities but acts to shield the Earth from ultraviolet radiation from the Sun. It is found in highest concentrations in the ozone layer.

ozone depletion [53] オゾン減損:

the process by which ozone in the atmosphere is irreversibly destroyed, mostly via interaction with CFCs.

ozone hole [53] 「オゾンホール」:

lower concentrations of ozone in the ozone layer over the Antarctic, particularly during spring.

ozone layer [40] オゾン層:

the layer in the stratosphere in which ozone concentrations are highest – usually found between 20 km and 30 km above the Earth’s surface.

parameterisation [120] パラメタリゼーション、パラメタ化:

in a weather forecast model, processes that occur on a scale smaller than that of the model grid cannot be directly represented. Instead, they must be accounted for statistically, or parameterised.

parcel of air [60] 「空気塊」:

a small mass of air that is assumed not to interact with the air around it – a useful model when explaining air movements.

partial pressure [44] 分圧:

the contribution to atmospheric pressure that is due to the molecules of a particular gas.

perihelion [66] 近日点:

the point of the Earth’s orbit when it is nearest to the Sun.

photons [51] 光子:

a small packet of energy that travels at the speed of light. Electromagnetic radiation can be considered a stream of such packets of energy.

photosphere [49] 光球:

the outermost layer of the Sun, which emits light.

photosynthesis [36] 光合成:

the process by which plants produce energy by converting carbon dioxide and water into oxygen.

pluvial flooding [110]: (大雨による洪水)

a type of flooding where excess rainfall causes more water to enter a river than it can cope with, resulting in the river bursting its banks.

polar cell [74]:

part of the three-cell model of atmospheric circulation. The polar cell consists of rising air in the mid-latitudes at the polar front and descent over the poles.

polar continental air mass [79] 「大陸性寒帯気団」:

a mass of air that originated over land at high latitudes.

polar front [74] 「極前線」、「寒帯前線」:

the boundary in the midlatitudes where warm tropical air meets cold polar air.

polar low [86]:

a type of low-pressure system that forms at high latitudes and tracks south, usually bringing heavy snowfall.

polar maritime air mass [79] 「海洋性寒帯気団」:

a mass of air that originated over the ocean at high latitudes.

polar orbit [32] 極軌道:

a satellite in a polar orbit travels around the Earth in a north–south direction, taking about 90 minutes to orbit the Earth once.

positive feedback [136] 正のフィードバック:

if a change in temperature affects a property of the atmosphere such that it enhances the temperature change, a positive feedback process is said to occur.

positive lightning [102] (正電荷の雷放電):

a positive lightning strike occurs when the base of the cloud adopts a negative charge. They are rarer than negative lightning strikes, although they tend to be more powerful.

precipitation [42] 降水、降水量:

a general term for water that falls from the sky, most commonly as rain, snow or hail.

pressure [8] 圧力、気圧:

atmospheric pressure is the force per unit area exerted by the atmosphere, usually expressed in pascals (Pa) or hectopascals (hPa).

pressure gradient force [68] 気圧傾度力:

the force on air parcels caused by pressure differences within the atmosphere.

pressure trend [21] 気圧の変化傾向:

any change in air pressure at a location over time.

primitive equations [120] 「プリミティブ方程式系」:

a set of basic physical equations that describe the behaviour of the atmosphere in space and time and form the basis of a weather forecast model.

probabilistic forecasting [123] 確率予報:

a probabilistic weather forecast uses many runs of a forecast model with slightly different initial conditions to give an idea of the probability of a certain weather type occurring.

profile [29]:

the variation of a certain aspect of the weather (such as temperature) along a vertical path through the atmosphere.

prognostic chart [124]:

a computer-generated chart, produced at various time steps through a forecast run, used to give an idea of how the weather is likely to change.

psychrometer [19] 乾湿球温度計:

a type of hygrometer that measures humidity using a dry-bulb thermometer and a wet-bulb thermometer. Humidity is determined by comparing the temperatures recorded on the two thermometers.

radar [13] レーダー:

a system of rainfall detection that uses pulses of radio waves (microwaves). These reflect off raindrops, giving information about both the location and the intensity of the rainfall.

radar reflectivity [30]:

the strength of a reflected radar signal as a fraction of the strength of the transmitted signal.

radiation [26] 放射:

the transfer of heat via the emission of electromagnetic waves.

radiation budget [50] 放射収支:

the balance of incoming radiation from the Sun and outgoing radiation emitted by the Earth–atmosphere system.

radiation fog [61] 放射霧:

fog generated by cooling of the surface by emission of thermal radiation. This cools the air above to its dewpoint, initiating condensation.

radiosonde [13] ラジオゾンデ:

an electronic device that is launched on a helium balloon and remotely returns observations of the weather conditions during its ascent.

radio waves [13] 電波:

electromagnetic radiation with very long wavelengths, used in radio transmissions. Short-wave radio waves (microwaves) are used in radar systems.

rain shadow [111]:

the tendency for an area downwind of mountains to receive less rainfall than an area upwind.

refraction [55] 屈折:

the change in direction of light as it passes between two different materials (for example, air and water).

regional model [121] 領域モデル:

a weather forecast model that runs on a limited area of the world at greater detail than a global model.

relative humidity [19, 44] 相対湿度:

a method of quantifying humidity in terms of mass of water vapour as a fraction of the maximum mass of water vapour that the air can hold.

remote sensing [29] リモートセンシング、遠隔観測:

the detection of weather conditions over large areas from a single, remote location (for example, using radar or satellites).

return stroke [102]:

the second stage of a lightning strike, where current flows along the path of ionised air generated by the leader stroke. The return stroke is substantially brighter.

ridge [78] 気圧の峰:

a long extension of high pressure.

rime [62]:

spikes of ice that freeze on a cold surface when the surface is exposed to freezing fog.

Saffir–Simpson Hurricane Scale [92]:

a scale used to describe the severity of tropical cyclones.

saturated adiabatic lapse rate [60] 飽和断熱減率:

the rate at which the temperature of a parcel of air will decrease per unit height if it rises adiabatically and the air is saturated.

scattering [51] 散乱:

the redirection of light from atmospheric molecules and particles.

sea breeze [106] 海風:

a light wind that blows from the sea to the land on a hot day, caused by the different properties of the land and sea surfaces.

sea breeze front [106] 海風前線:

the advancing edge of a sea breeze, where the maritime air encroaches on the air over land.

seasonal forecast [128] 季節予報:

a forecast that predicts the general weather conditions over an entire season.

seeder-feeder effect [109]:

an effect that leads to more intense rain in hills and mountains. When rain falls through cap clouds, the raindrops grow by coalescence, resulting in much heavier rain than would fall in the absence of a cap cloud.

sensitivity [137] 感度:

climate sensitivity is the effect on the change in global temperature caused by a change in the magnitude of a certain climate forcing.

sheet lightning [102]:

lightning that passes between charged regions within a thundercloud, illuminating the cloud from within.

single-cell storm [102]:

a thunderstorm that consists of a single cumulonimbus cell.

sirocco [113]:

a warm wind that blows across the Mediterranean from North Africa to France and Italy.

smog [114]:

a smoky layer of fog that can form in polluted conditions.

solar radiation [50] 太陽放射、日射:

radiation that has originated from the Sun – mostly consisting of visible light and ultraviolet radiation.

solarimeter [26] 日照計 (の一種):

a device that measures the intensity of sunlight reaching the Earth’s surface. It can also be used to infer sunshine duration.

sounding [29]:

a set of measurements from a radiosonde that sample the atmosphere along a vertical path.

Southern Oscillation [95] 「南方振動」:

the fluctuation of ocean temperatures between El Niño and La Niña conditions, which affects wind flow patterns and rainfall over the tropical Pacific Ocean. It also has far-reaching impacts on weather conditions elsewhere in the world.

specific humidity [44] 比湿:

a method of quantifying humidity in terms of mass of water vapour per unit mass of air.

squall line [103]:

an organised line of storms that can bring gusty winds and heavy showers.

stability [61] 安定度、安定性:

a measure of how susceptible the atmosphere is to cloud formation. In an unstable atmosphere, clouds form readily; in a stable atmosphere, cloud formation is suppressed.

station pressure [20] 現地気圧:

the air pressure recorded at a weather station before correction for its altitude above mean sea level.

Stevenson screen [18] 百葉箱:

a ventilated box used to house thermometers and psychrometers as part of a weather station.

sting jet [86]:

a strong, descending flow of air found in the centre of some severe mid-latitude depressions, which can cause damaging winds at the surface.

storm surge [95] 高潮:

a rise in sea level under a severe low-pressure system, which can cause flooding in low-lying coastal areas.

storm tracks [75]:

the paths frequented by mid-latitude depressions.

stratiform clouds [61] 層状の雲:

a generic term for clouds that form in sheets over large areas. These form in stable conditions, or at weather fronts, and include stratocumulus, stratus and nimbostratus.

stratocumulus [23] 層積雲 (十種雲型):

a low-level liquid water cloud consisting of a layer of individual cells.

stratopause [40] 成層圏界面 (成層圏の上端):

the temperature maximum found at the top of the stratosphere.

stratosphere [40] 成層圏:

the layer of the atmosphere above the troposphere, marked by increasing temperature with height and containing the ozone layer.

stratus [23] 層雲 (十種雲型のばあいと広い意味のばあいがある):

a low-level liquid water cloud that has a grey and uniform appearance and sometimes brings drizzle.

street canyon [114]:

a street bordered on each side by tall buildings, which can channel the wind in urban areas.

sub-tropical highs [72] 亜熱帯高気圧:

the areas of high pressure and dry conditions associated with the descending branches of the Hadley cells, found approximately 30° either side of the Equator.

sundogs or parhelia [55] 「幻日」:

patches of dispersed light that can sometimes be seen on a horizontal plane either side of the Sun. They are caused by the refraction of light in ice crystals. Similar patches around the Moon are referred to as moondogs.

supercell [103]:

a vast, rotating convective system that can persist for long periods of time and bring damaging winds, hail, thunder, lightning and tornadoes.

supercooled liquid water [46] 過冷却水:

liquid droplets in the atmosphere that have formed at temperatures below 0°C.

supersaturation [44] 過飽和:

air with a relative humidity over 100% is said to be supersaturated.

surface temperature [58] 地上気温 (地表面温度をさすばあいもある):

the temperature of the air in the lowest few metres of the atmosphere.

synoptic observations [17] (下の記述はイギリス気象庁の観測の分類としての意味らしい):

a set of observations that are reported frequently (usually hourly) throughout the day and night.

teleconnections [96] 「テレコネクション」:

remote impacts of the weather conditions in one location on weather conditions in a different part of the world.

temperature [38] 温度:

a measure of how hot or cold an object (or mass of air) is. On a molecular level, it is related to the speed at which the molecules move.

temperature inversion [31] (温度)逆転、逆転層:

a location in the atmosphere where temperature increases with height.

temperature proxy [132]:

something that gives an indication of past temperature, such as tree rings and ice cores.

thermal [60] 「サーマル」:

a rising plume of air that is warmer than its surroundings.

thermal (or terrestrial) radiation [50] 熱放射、地球放射:

infrared radiation that has been emitted by the Earth or the atmosphere.

thermistor, thermocouple [26] サーミスタ、熱電対 (前者は抵抗が温度による。後者は起電力が温度差による。):

types of small electronic sensors that are used to measure temperature.

thermodynamics [11] 熱力学:

the transformation of heat into different types of energy.

thermometer [8] 温度計:

a term for any device that measures temperature.

thermosphere [41] 熱圏:

the low-density outer layer of the atmosphere where temperature increases with height.

tipping-bucket rain guage [22] 転倒ます式雨量計:

a type of rain gauge that collects rainfall in a countainer mounted on a pivot. When the rainfall accummulation exceeds a certain threshold, the container tips over and the tip is recorded.

TIROS-1 [13]:

the first successful weather satellite, launched by NASA in 1960.

tornado [104] たつまき、トルネード:

a rapidly rotating column of air that extends from the bottom of a severe convective storm system.

Tornado Allay [104] 「たつまき街道」:

a stretch of the central and eastern USA where supercells and tornadoes tend to form.

total solar irradiance [51] 全波長太陽放射照度。いわゆる「太陽定数」のかわりにもつかわれる。:

the total amount of incident energy from the Sun per unit area at the top of the atmosphere.

trade winds [72] 貿易風:

the easterly, Equatorward winds associated with the Hadley cells in the tropics.

triple point [80] 三重点:

in a mature mid-latitude depression, this is the point where the warm front, cold front and occluded front meet.

tropical continental air mass [79] 「大陸性熱帯気団」:

a mass of air that originated over land in the tropics.

tropical cyclone [92] 熱帯低気圧 (そのうち強いものをさす。):

a tropical depression whose winds exceed 33 m/s. In different parts of the world, they are known as hurricanes or typhoons.

tropical depression [92] 熱帯低気圧 (そのうち弱いものをさす。):

a low-pressure system that forms in the tropics, normally consisting of a mass of convective activity.

tropical maritime air mass [79] 「海洋性熱帯気団」:

a mass of air that originated over the ocean in the tropics.

tropical storm [92] 熱帯低気圧 (強さの階級をわけてしめすばあいは、TDとTCの中間):

a tropical depression whose winds exceed 16 m/s.

tropics [88] 熱帯:

the part of the Earth where the weather is governed by the Hadley circulation, typically extending about 30° either side of the Equator.

tropopause [40] 対流圏界面、圏界面:

the temperature minimum at the top of the troposphere.

troposphere [27] 対流圏:

the layer of the Earth's atmosphere nearest the surface, marked by decreasing temperature with height and containing most of the weather we experience.

trough [78] 気圧の谷:

a long extension of low pressure.

turbulent flow [40] 乱流:

in a fluid, turbulent flow is characterised by disorganised motion in eddies and vortices.

typhoon [92] 台風:

a name for tropical cyclones that form in the western Pacific.

ultraviolet radiation [49] 紫外線(の放射):

electromagnetic radiation with wavelengths between about 10 nm and 400 nm; a component of solar radiation.

Universal Time Co-ordinated (UTC) [16] 協定世界時、世界時:

the time convention used by meteorologists all over the world. UTC is fixed to Greenwich Mean Time.

unstable [121] 不安定な:

in a weather forcast model, unstable activity causes the model to fail and produce unrealistic results. In the atmosphere, unstable conditions lead to rapid cloud development.

updrought [99] (アメリカつづり updraft) 上昇流:

the ascending column of air at the heart of a convective storm system.

upper air [27] 上空の、「高層」(観測):

a term for the mid-to-high troposphere.

urban heat island effect [115]:

the enhanced temperatures found in an urban area that occur both during the day and at night.

validation [136] 「検証」(の一種):

the verification of the performance of a weather or climate model by running it over a period where the weather conditions are known and checking its ability to reproduce there conditions.

vapour pressure [44] (アメリカつづり vapor ...) 水蒸気圧:

the contribution to atmospheric pressure that is due to the molecules of water vapour.

veering [20]:

the wind is said to be veering if it is changing in a clockwide direction (for example, from southerly to westerly).

visibility [23] 視程:

the furthest distance at which objects can still clearly be seen.

Walker circulation [95]:

the east-west circulation of air over the tropical Pacific which varies with phase of the Southern Oscillation.

wall cloud [105]:

the mass of cloud that encircles the updrought in a supercell and indicates a region where tornadoes are most likely to form.

warm conveyor belt [85]:

one of the three air streams that maintains a mid-latitude depression, consisting a stream of warm air that rides up the warm front.

warm-core anticyclone [79]:

a type of anticyclone containing a deep column of descending air in its centre.

warm front [80] 温暖前線:

a boundary where a mass of warm air rides up over a mass of colder air, leading to ascent and cloud development.

warm sector [84]:

the area between the warm and cold fronts in midl-latitude depression that contains warm, moist air.

water vapour [36] (アメリカつづり ... vapor) 水蒸気:

water in the atmosphere in gaseous form.

waterspout [105]:

a tornado over the sea.

weather lore [7] 天気ことわざ:

a set of sayings, based on natural indicators, traditionally used to give rudimentary weather forecasts.

well-mixed gases [36]:

most gases found in the atmosphere are said to be well-mixed as they exist in the same percentages in the lowest 100 km.

wet-bulb thermometer [18] 湿球温度計:

a thermometer whose bulb is kept moist and is used in combination with a dry-bulb thermometer to measure humidity.

wind shear [80]:

a change of wind speed and direction with height.

World Meteorologial Organiztaion (WMO) [16] 世界気象機関:

a branch of the United Nations that enables worldwide co-operation in weather observation and forecasting.

yellow dwarf star [49]: 「黄色矮星」 (これは星を「巨星」と「矮星」だけにわける観点による表現だろう。 わたしは太陽を巨星でも矮星でもなく主系列星だと言う。)

an astronomical category of star that includes the Sun.

• Jon Shonk, 初版 2013, 第2版 2020: Introducing Meteorology -- A Guide to Weather (Second Edition). Edinburgh: Dunedin Academic Press Ltd., 160 pp. ISBN 978-1-78046091-8 (paperback), 978-1-78046643-9 (Epub), 978-1-78046645-3 (PDF). 出版社サイトの本書のページ　https://dunedinacademicpress.co.uk/page/detail/Introducing-Meteorology/?K=9781780460918 [読書メモ]