How much water in the hydrosphere?Conventional estimate assumesa total groundwater storage of about 1,700 quadrillion gallons. This gives the estimate of hydrosphere’s total water content as 3.5x1020 gallons.

Oceans (97%)

Ice (1.2%)

Underground water (0.5%)Surface water (0.02%)

Atmosphericmoisture (0.001%)

An alternate assumption is that pores in sediments contain about 80,000 quadrillion gallons of groundwater (almost 50 times the conventional estimate). This yields an estimate of about 4x1020 gallons of water in the entire hydroshere.

Oceans (80%)

Ground-water (19%)

Groundwater (19%)

Ice (1%)Surface water (0.002%)

Atmosphere(0.001%)

0

1

2

3

4

5

6

0 1 2 3

% A

nnual GW

P C

hange (5-year smoothing)

% Annual Population Change(5-year smoothing)

0

4

6

1900 1925 1950 1975 2000

0

1

2

3

(5-y

ear

sm

oo

thin

g)

% A

nn

ual G

WP

Ch

an

ge

(5-y

ear s

mo

oth

ing

)%

An

nu

al P

op

ula

tion

Ch

an

ge

World’s rate of economic growth has been declining, after a spurt during 1950-70, but

has been about twice that of the population,

with which it correlates posi-tively (R = 0.89)

Farming (41%)Public(10%)

Industry(11%)Power-

Plant (38%)Farming (85%)

Public (6%)

Industry(7%)

Power-Plant (2%)

U.S.A. China

As is evident from the comparison of water use in the U.S. and China, economic growth necessitates increasing use of water for power generation.

Source: Worldwatch Institute

Tem

per

atu

re C

han

ge

(C

)o

0.6

0.3

- 0.3

0.0

- 0.61900 1950 2000

Global mean temperature change through the past

century

Source: NOAA and NASA

5-yearrunningaverage

Se

a l

ev

el

rela

tiv

e t

o 1

95

1-7

0 (

cm

)

8

0

4

-12

-8

-4

1900 20001950

5-yearrunningaverage

The global mean sea-level rise through last

century

Source: T.P. Barnett, in CLIMATE CHANGE (IPCC Working Group Report: Cambridge University Press, 1990)

Steric height (dynamic cm

)

Distance off California coast (km)500 400 300 200 100 0

100

95

90

85

80

1985-91

1950-56

0

100

200

300

400

500

0 0.3 0.6 0.9 1.2T (oC)

Dep

th (m

)The 1950-91 hydrographic data off California coast show that

sea surface waters (0-100m) became~0.8oC warmer in the 35-year period between 1950-56 and 1985-91; which

raised the sea level sur-face by 3.1+0.7 cm.

Note: Warming by 1oC the top 100 m of ocean with 15oC temperature and 3.4% salinity should raise the sea level by ~2.2 cm.

Source: D. Roemmich, SCIENCE: v. 257, p.373-375 (July 17, 1992).

Number of Fatalities per Event3 30 300 3,000

3

0.3

0.03

Tornadoes

FloodsTornadoesHurricanesEarthquakes

Cu

mm

ula

tiv

e N

um

be

r o

f E

ve

nts

pe

r Y

ea

r

0.1

1

10

0.011 10 100 1,000 10,000

Floods

Hurricanes

Earthquakes

U.S. 20th Century Natural Disaster Fatality-Frequency Plots*

* S.P. Nishenko and C.C. Barton: “Scaling Laws for Natural Disaster Fatalities” in REDUCTION AND PREDICTABILITY OF NATURAL DISASTERS (Eds: Rundle, Turcotte and Klein) (Addison-Wesley, 1996)

* International Federation of Red Cross and Red Crescent Societies (The Economist, Sept 6, 1997)

High wind: 21%

Earthquake: 8%

Flood: 19%

Other naturaldisasters: 21%

Volcanoes: 1%

Drought & Famine: 6%Landslides: 3%

Man-madedisasters: 34%

Disasters*by type: 1971-96

Total: 8,219,000

0

2

4

6

1800 1850 1900 1950 2000Source: A. Maddison, Monitoring the World Economy 1820-1992 (OECD, Paris, 1995).

Wo

rld

Po

pu

lati

on

(in

bil

lio

ns)

World’s population, a little over a billion at the time of Malthus, has multiplied over five-fold since then.

0

10

20

30

1800 1850 1900 1950 2000Source: A. Maddison, Monitoring the World Economy 1820-1992 (OECD, Paris, 1995).

Gro

ss

Wo

rld

Pro

du

ct

(tri

llio

n 1

99

0$

)Measured in inflation-adjusted 1990 dollars, world’s total output, now about $30 trillion, was about $700 billion at the time of Malthus.

18000

15

30

45

1850 1900 1950 2000

Rel

ativ

e to

th

e 18

20 l

evel

Source: A. Maddison, Monitoring the World Economy 1820-1992 (OECD, Paris, 1995).

Economy

Population

Clearly, economic growth has been more strongly exponential than that of the demand (population growth) that created it.

0.5

1.0

1.5

2.0

1940 1960 1980 2000

100

200

300

400

Pe

r Ca

pita

Gra

in A

va

ilab

ility (k

g p

er y

ea

r) Wo

rld

Gra

in P

rod

uc

tio

n (

bill

ion

to

ns

pe

r y

ea

r)Despite the tremendous strides in world grain production, per capita grain availability has remained unchanged since the mid-1970s.

Source: WORLDWATCH INSTITUTE (State of the World, 1997)

Source: A. Maddison, Monitoring the World Economy 1820-1992 (OECD, Paris, 1995).

World

Pop

ulation

(billion

)

Gross W

orld P

rodu

ct (trillion 1990$)

1800 1840 1880 1920 1960 20000

2

4

6

0

10

20

30

0

2

4

6

1800 1850 1900 1950 2000

% A

nn

ual

Gro

wth

WorldPopulation

Gross WorldProduct

World population has

grown five-fold, since 1820, but

economic growth has been

eight-times faster.

Thank You!

Wolf population

1900

3000

4000

5000

1000

200050

30

40

20

10

1920 198019601940 20000

Wolves and Moose at the Isle Royale National Park, Lake Superior - an example of “sustainable growth”

Wolf population

1900

3000

4000

5000

1000

200050

30

40

20

10

1920 198019601940 20000

0

15

30

Mean annual precipitation (cm)

0 400

Tropical Forest

Des

ert G

rass

land

Arctic and alpinetreeless areas

100 200 300

Mea

n A

nnua

l Tem

pera

ture

(C

) o

Farmland

Coniferous Forest(green year-round)

Deciduous Forest(seasonal loss of leaves)

Farmland, generallyin short-supply,imposes arestricted range of precipitation and temperature conditions.

SELF-ACTUALI-ZATION

SOCIAL

SECURITY

PHYSIOLOGICAL

ESTEEM

Food is the most basic of allour needs

MASLOW’S HIERARCHY OF NEEDS

0 4 8 12 16

ETHIOPIA

CHINA

BANGLADESH 31.9

SUDAN

48.4

DISASTER FATALITIES* (1971-95: IN THOUSANDS)

MOSTLY FLOODS

MOSTLY FAMINE

MOZAMBIQUE

MOSTLY MASS STARVATION

INDIA

SOVIET UNION/CIS STATES

IRAN

PHILIPPINES

NICARAGUA

COLUMBIA

GUATEMALA

SOMALIA

NIGERIA

PERU

MEXICO

HONDURAS

* International Federation of Red Cross and Red Crescent Societies (The Economist, Sept 6, 1997)

90o N

0o

30o N

60o N

90o S

30o S

60o S

Lat

itu

de

5 10 15 20

Land

Whole Earth

Oceans

Surface Area (million km2)

25

90o N

0o

30o N

60o N

90o S

30o S

60o S

Lat

itu

de

5 10 15 20

Land

Whole Earth

Oceans

Surface Area (million km2)

25

0.1

1

10

0.011 10 100 1,000 10,000

Floods

Hurricanes

Earthquakes

80

85

90

95

100

0100200300400500

Distance off California coast (km)

Ster

ic he

ight (

dyna

mic c

m)

Dean Roemmich: Ocean warming and sea level rise along the southwest U.S. coast [Science: 257 ( 373-375), 1992]

1985-1991

1950-1956

Sea surface off California has risen by about 2 cm, on average, between 1950 and 1991

Convergent boundaryDivergent boundary

Tranform faults, rift valleys etc.

VolcanoFlood basalt

SiberianTraps

DeccanTraps

Icelandicvolcanism

ParanaBasalts

ColumbiaRiver Basalts

Hawaii

75%

50%

25%

0%

Rhyolite BasaltAndesite

K-Feldspar

Quartz