What is cloud seeding? Step-by-step graphic 明らかにする／漏らすs how the 天候 modification technique 作品 - as 専門家s question whether it was to 非難する for the Dubai floods

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On Tuesday, the 部隊d Arab 首長国s was 攻撃する，衝突する with a year and a half of rain in a 選び出す／独身 day, leaving much of Dubai underwater.

Now, 専門家s have questioned whether the 砂漠 city's sudden deluge might have been 原因（となる）d by 気候 干渉.?

Since the 早期に 1990s, the UAE has used a technique called cloud seeding to 上げる its 年次の 降雨 and 上げる 供給（する）s of drinking water.?

This technique sees specialised salt ゆらめくs 解放（する）d from 計画（する）s, before 飛行機で行くing inside clouds to 誘発する／引き起こす 降雨.

So, as Dubai 直面するs its most 厳しい rain on 記録，記録的な／記録する MailOnline takes a step-by-step look at how the 議論の的になる technique 作品.?

Cloud seeding 作品 by 解放（する）ing 穀物s of salt or silver iodide into clouds, these 誘発する／引き起こす water vapour to condense or 凍結する into droplets big enough to 落ちる as rain?

Since the 早期に 1990s the UAE has been using this 議論の的になる technique to 増加する 降雨 by around 15-25 per cent. Shown here is a UAE 計画（する） 解放（する）ing salt ゆらめくs within a cloud

Controlling the 天候 might sound like futuristic 科学（工学）技術, but the 原則 was 現実に discovered as far 支援する as the 1940s.?

Scientists from General Electric?設立する that water 冷静な／正味のd to between 14°F (-10°C) and 23°F (-5°C) couldn't form ice 水晶s under some lab 条件s.?

The water couldn't 凍結する because there was no '核' for the ice 水晶 to form around.?

However, when the scientists 追加するd silver iodide to the water vapour they 設立する that the ice 水晶s formed 即時に.?

In nature, clouds produce rain or snow when water vapour forms around natural nuclei like bacteria or dust.

What the scientists had discovered was an 人工的な way of 追加するing nuclei to clouds which could 誘発する／引き起こす the vapour to 速く condense.??

Although the 科学（工学）技術 has come a long way, modern cloud seeding uses the same basic ideas that were developed 80 years ago.?

Dr Brian Thomas, an 専門家 in hydrology from UCL, told MailOnline that natural 降雨 has four 行う／開催する／段階s.

First, the 空気／公表する is 冷静な／正味のd to the 'dew point' as warm 空気／公表する rises into the 冷淡な atmosphere.

Second, that water vapour condenses around a 'cloud condensation nuclei' (CCN).

Third, those 減少（する）s then get larger until they are 激しい enough to 落ちる.

And, finally, the atmosphere '輸入するs' more water to the area to keep the rain flowing.?

Dr Thomas said: 'Cloud seeding 行為／法令／行動するs on step two. 化学製品s are 分散させるd in the upper atmosphere to 行為／法令／行動する as CCNs, thus kickstarting the rain 形式 過程.'

As long as there is 冷静な／正味の moisture vapour in the atmosphere and more moisture keeps 存在 輸入するd, the r ain will continue.??

Not every cloud can be seeded so the UAE's?国家の 中心 of Meteorology 持続するs a (n)艦隊／(a)素早い of 計画（する）s (pictured) that can 答える／応じる when a suitable cloud is spotted?

Not every cloud is 権利 for seeding so the NCM has 設立するd a sophisticated 網状組織 of 測候所s to 監視する atmospheric 条件s.?

The UAE's Rain Enhancement Program (UAEREP) said: 'The NCM has 設立するd a 国家の 網状組織 of 86 (a)自動的な／(n)自動拳銃 測候所s (AWOS) for 天候 監視するing, six 天候 レーダs covering the entire UAE, and one upper 空気／公表する 駅／配置する.'

Once the 権利 肉親，親類d of cloud is spotted, specialised seeding 計画（する）s are 緊急発進するd to 答える／応じる.?

示す Newman, 副 長，指導者 操縦する at NCMS, 以前 told MailOnline: 'As soon as they see some convective cloud 形式s, they 開始する，打ち上げる us on a flight to 調査／捜査する.'

The 計画（する）s are 負担d with salt ゆらめくs that can be 燃やすd ーするために 誘発する／引き起こす 増加するd 降雨

It is 概算の that the UAE 飛行機で行くs around 1,000 hours of seeding flights every year, although it is uncertain just how much this 現実に changes rain patterns?

If the 条件s are believed to be 訂正する, the 操縦するs will 解雇する／砲火／射撃 hygroscopic ゆらめくs which 解放（する） a 罰金 砕く of salt into the cloud.

While silver iodide is used どこかよそで, salt 作品 井戸／弁護士席 in warmer 気候s and 達成するs the same 影響.

The water vapour then condenses around 粒子s of salt and becomes larger and heavier.?

Once they reach a 確かな size, the water droplets then 落ちる as rain, snow, or あられ／賞賛する depending on the 天候 条件s.?

It is believed that the AUE 飛行機で行くs around 1,000 hours of seeding flights each year to 増加する 降雨 in this way.?

In some 事例／患者s, rather than 飛行機で行くing 計画（する）s into clouds, seeding can also be done by 解雇する／砲火／射撃ing seeding ミサイルs from the ground.?

In 中国, this technique has been used to コースを変える 降雨 away from rivers as part of a 干ばつ 救済 成果／努力 and 報道によれば to 避ける rain during the 2008 Olympics.

In 中国, misiles 含む／封じ込めるing seeding スパイ／執行官s have been 解雇する／砲火／射撃d into clouds as a 代用品，人 for 飛行機で行くing seeding 計画（する）s?

On Tuesday much of Dubai (pictured) was 急落（する），激減（する）d underwater by the worst flooding on 記録，記録的な／記録する?

Cars have been swept away and 輸送（する） paralysed as the 資本／首都 city 取引，協定s with a year and a half of rain in 24 hours?

すぐに after flooding 攻撃する，衝突する, questions began to be raised as to whether cloud seeding had been responsible.?

Ahmed Habib, a specialist 気象学者, 最初 told Bloomberg that?at least seven seeding 計画（する）s from Al Ain airport between Sunday and Monday.?

However, the NCM 速く 否定するd that any cloud seeding 操作／手術s had taken place at all in the lead-up to the 激しい 降雨.

Omar AlYazeedi, 副 director general of the NCM, told CNBC?that the 会・原則 'did not 行為／行う any seeding 操作／手術s during this event.'

Mr AlYazeedi 追加するd: 'One of the basic 原則s of cloud seeding is that you have to 的 clouds in its 早期に 行う／開催する／段階 before it rains, if you have a 厳しい 雷雨 状況／情勢 then it is too late to 行為／行う any seeding 操作／手術.'

Some have 非難するd cloud seeding for the 増加するd 降雨 although the NCO 否定するs that any seeding took place?

にもかかわらず the UAE's たびたび（訪れる） use of cloud seeding, there are still 疑問s の中で some 専門家s as to whether it could 増加する 降雨 to this extent.

Between Monday morning and the end of Tuesday Dubai received more than 5.9 インチs of rain.

An 普通の／平均（する） year sees 3.73 インチs of 降雨 at Dubai International Airport, meaning the country received a year and a half of rain in 24 hours.

The country is one of the driest in the world, receiving between 140 and 200mm of rain per year.

However, during this week's 激しい downfall the 首長国 of Al Ain received more than 250mm in one go.??

熟考する／考慮するs have 示唆するd that cloud seeding 一般に 増加するs 降雨 by around five to 15 per cent on 普通の／平均（する）, far いっそう少なく than the extreme deluges seen this week.

In 新規加入, cloud seeding 一般に takes place away from 居住させるd areas 予定 to 領空 制限s.?

This means it is not （疑いを）晴らす whether 増加するd rain over Dubai could have been 原因（となる）d by any cloud seeding 操作／手術s taking place どこかよそで.??