disaster (n)
/dɪˈzɑː.stər/

an event that results in great harm, damage, or death, or serious difficulty

tornado (n)
/tɔːrˈneɪ.doʊ/ 

a very strong wind that goes quickly round in a circle or funnel

eruption (n)
 /ɪˈrʌp.ʃən/

a phenomenon of starting suddenly and violently

hurricane (n)
/ˈhɝː.ɪ.keɪn/

a violent wind that has a circular movement

drought (n)
/draʊt/

a long period when there is little or no rain

avalanche (n)
/ˈæv.əl.ɑːnʃ/ 

a large amount of ice, snow, and rock falling quickly down the side of a mountain

erosion (n)
/ɪˈroʊ.ʒən/

the fact of soil, stone, etc. being gradually damaged and removed by the sea, rain, or wind

exhaust fumes (noun phrase)
/ɪɡˈzɔːst fjuːmz/

gas or flue gas is emitted as a result of the combustion of fuels such as natural gas, gasoline/petrol, diesel fuel, fuel oil or coal

iceberg (n)
/ˈaɪs.bɝːɡ/

a very large mass of ice that floats in the sea

snowstorm (n)
/ˈsnoʊ.stɔːrm/

a heavy fall of snow that is blown by strong winds

hailstorm (n)
/ˈheɪl.stɔːrm/

a sudden heavy fall of hail

flood (v)
 /flʌd/

to cause to fill or become covered with water

earthquake (n)
/ˈɝːθ.kweɪk/

a sudden violent movement of the earth's surface, sometimes causing great damage

volcano (n)
/vɑːlˈkeɪ.noʊ/

a mountain with a large, circular hole at the top through which lava (= hot liquid rock) gases, steam, and dust

tsunami (n)
/tsuːˈnɑː.mi/

an extremely large wave caused by a violent movement of the earth under the sea

forest fire (n)
/ˈfɔːr.ɪst faɪr/

an uncontrolled fire in a large wild area of trees

landslide (n)
/ˈlænd.slaɪd/

a mass of rock and earth moving suddenly and quickly down a steep slope

acid rain (n)
/ˈæs.ɪd reɪn/

rain that contains large amounts of harmful chemicals as a result of burning substances such as coal and oil

hoarfrost (n)
/ˈhɔːr.frɑːst/

a white layer of pieces of ice like needles that forms on objects outside when it is very cold

the greenhouse effect (n)
/ðə ɡriːn.haʊs ɪˈfekt/

an increase in the amount of carbon dioxide and other gases in the atmosphere