Page 93 - The World About Us

Vic ms of drought
1.1.1
1.1.1
2.2.3
2.3.5

What has been the global impact of drought?

Most droughts begin as a result of the ITCZ and STHP can impact large Drought is felt worldwide
of changes to regular climate areas of Africa. Should the ITCZ not
pa erns. In Europe, this may be the move as far north as usual, areas of In recent years droughts have affected many
result of large, stable, high-pressure the Sahel may receive less rain than areas of the world including:
systems which can block rain-bearing normal, ini a ng a drought. Middle East, from 1998 Since 1998 parts of
depressions from moving in off the Many climatologists have the Eastern Mediterranean have been in the worst
Atlan c Ocean. drought for 900 years, according to tree ring
predicted that droughts may become analysis by NASA climate scien sts. This drought
In many parts of the world El Niño more frequent and more prolonged, has also affected Southern European countries.
and La Niña influence drought. El as a result of climate change. Brazil, 2014-16 The South American na on
Niño events see drought over South Computer modelling suggests that experienced its worst drought for 80 years. Water
Asia, Southern Africa and Australia, while some places may see a small was ra oned in São Paulo, where its main reservoir
while La Niña brings droughts to Peru. decrease in drought frequency, others dropped to just 6% of its total capacity.
may experience much deeper and
Changes to the rela ve posi ons China, 2014-16 The north-east of China
longer droughts in years to come.
experienced its worst drought on record. This
reduced agricultural produc on and created severe
food shortages in mega-ci es such as Beijing.
Mongolia, 2017 A long-term drought has led
to tens of thousands of Mongolian herdsmen giving
up their tradi onal lifestyles and moving their yurts
to the capital, Ulaanbaatar. In 2017 the
government suspended grain exports on the
expecta on of a very poor harvest.
India, 2016-17 A severe drought across many
states in India saw some states fail to receive their
expected monsoon rains. Reservoirs fell
drama cally to just 20% of capacity. In
Karnataka state, 1,100 farmers were reported to
have commi ed suicide in despera on.
Fig.248 Fish le stranded by falling water levels during a California drought. South East Asia, 2016 Thailand suffered its
worst drought in decades, reducing rice produc on
What is the role of the ITCZ? The Inter-Tropical Convergence Zone and raising food prices. Vietnam saw the River
(ITCZ) is responsible for bringing low Mekong fall to its lowest level in many years,
pressure and heavy rainfall to the tropical regions over which it has influence reducing farm yields and causing salt
(see pages 6 and 86). The ITCZ moves throughout the year because the Earth’s contamina on in the Mekong Delta. Wildfires
lt changes the rela ve posi on of the overhead Sun. The posi on of the ITCZ destroyed crops in the Malaysian province of
is also influenced by land and sea temperatures and mountain ranges. Sabah, Borneo. East Timor saw one third of its
popula on affected by drought. In Indonesia 16
Should the ITCZ not move as far north or south one year, it may leave a
of the 34 provinces were affected, with crops
region without its annual rainy season. Land that has been parched under the
suffering or failing completely from West Java
Sub-Tropical High Pressure (STHP) may not receive the rainfall needed to through Bali and the islands of Nusa Tenggara.
replenish soil moisture. The drought will last un l the ITCZ returns the In the Philippines a ‘state of calamity’ was declared
following year bringing convec onal rainfall in its wake. in 17 areas, with crop damage es mated at around
US$20 million.
Fig.249 The posi on of the Inter-tropical Convergence Zone, December and June.
Fig.250 Drought dries up Australia’s Murray River.

December ITCZ June ITCZ

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Extreme weather conditions cause different natural weather hazards.