外研版（2019）必修 第三册Unit 2 Making a difference Understanding ideas课件(图片版 共21张PPT)

(共21张PPT)
B3U2 Making a difference
Period 2 Understanding ideas
The well
that changed
the world
RYAPS WELL
Look and talk:
Look at the map and talk about water problems in Africa.(P18-1)
What is it about
What do different colours stand for
Water scarcity in Africa
Water scarcity remains a serious issue in parts of Africa
for years,especially in North Africa.In Africa,millions of
people can't get access to clean drinking water,and they
are living in areas with poor sanitation services.
in Africa by 2025
cubic meter方米'
Freshwater shortage(less than 1,000 m3/capita/year)
Freshwater stress(1,000 to 1,700 m3/capita/year)
Globally,renewable internal freshwater resource per
capita was around 6,000 m3in 2014.
Moreover,water availability,access
and optimal use in Africa are not
promising.Only 5%of Africa's
cultivated land is irrigated and less than 10%of hydropower
potential is utilized for electricity generation.
The reasons for water scarcity in Africa are complicated.
●
Frequent droughts due to global warming and deforestation have
shrunk lakes and changed rainfall patterns.
Traditional irrigation technology and agriculture have caused a good
sum of water waste.
Growing population and urbanization have increased the domestic
and industrial water consumption,which can't be fully supported by
poor infrastructure