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UNIT 1: WHERE DO WE STAND? THE STATE OF THE GLOBAL ENVIRONMENT
Measures of poverty
Many millions of
people still suffer
from different
forms of poverty;
more than 1,300
million are
‘income-poor’
and have to live
on less than
US$1/day
malnourished
children
people not expected
to survive to age 40
people lacking
health services
illiterate adults
people lacking
safe water
people who are
income-poor
millions
0 200 400 600 800 1,000 1,200
Source: UNDP 1997/Published in Global Environment Outlook 2000, UNEP
Human development index
UNDP’s Human
Development
Index is a
composite index
based on life
expectancy,
educational
attainment and
income
HDI value 1994
0.90
0.80
0.70
0.60
0.50
0.40
0.30
0.38
Sub-
Saharan
Africa
0.65
East
Asia
0.46
South
Asia
0.67
Southeast
Asia
and the
Pacific
0.64
Arab
States
0.83
Latin
America
and the
Caribbean
0.76
Eastern
Europe
and CIS
0.91
Industrial
Countries
0.76
World
S
E
C
T
I
O
N
1
Source: UNDP 1997/Published in Global Environment Outlook 2000, UNEP
1.1 Global Warming and Climate Change
The earth’s atmosphere is getting warmer. The United Nations Environment
Programme reports that the average global temperature, 15°C, has increased by
0.3° to 0.6° since the late 19th century, while thermal expansion of the oceans has
caused sea levels to rise by 10 to 25cm in the same period. The 11 warmest years
of this century have all occurred during the 1990’s, with 1997 being the warmest
so far.
Global warming, or the ‘greenhouse effect’, is a natural atmospheric feature.
The earth’s surface absorbs radiation from the sun and re-radiates it into the
atmosphere. Radiatively active gases, or ‘greenhouse’ gases, absorb some of this
thermal radiation. If this did not occur, the earth’s average temperature would
be minus 18ºC. Human industrial activities, however, are substantially increasing
the atmospheric concentrations of greenhouse gases. This enhances the natural
greenhouse effect, causing additional warming of the earth’s atmosphere. This
is called ‘global warming’. The main gases that absorb thermal radiation and
increase global warming are carbon dioxide (CO2), methane (CH4), nitrous oxide
(N2O), the CFCs, ozone (O3) and water vapour.