Improving the Sustainability of the Living Earth

International Geosphere-Biosphere Programme

The Challenges for the Next Decade of IGBP Science

Carlos A NobreChair of IGBP and CPTEC-INPE

But, we need to put the puzzle together

Outline• Major milestones in Earth system

Research

• The Earth as a Complex System

• The New IGBP

• Stewardship of the Earth System

Part 1.Major Milestones in Earth

System Research

Svante Arrhenius:The First Climate Prediction

• Arrhenius quantifies in 1896 the changes in surface temperature (approx. 5 C) to be expected from a doubling in CO2, based on the concept of ”glass bowl” effect introduced in 1824 by Joseph Fourier

THE LONDON, EDINBURGH AND DUBLIN

PHILOSOPHICAL MAGAZINEAND JOURNAL OF SCIENCE

[FIFTH SERIES APRIL 1896]

XXXI. On the Influence of Carbonic Acid in the Air upon the Temperatureof the Ground. By Prof. SVANTE ARRHENIUS*.

1. Introduction: Observations of Langley on Atmospherical Absorption.

A GREAT deal has been written on the influence of the absorption of the atmosphere upon the climate. Tyndall † in particular has pointed out the enormous importance of this

question. To him it was chiefly the diurnal and annual variations of temperature that were lessened by this circumstance. Another side of the question, that has long attracted the

attention of physicists, is this: Is the mean temperature of the ground in any way influenced by the presence of heat-absorbing gases in the atmosphere? Fourier ‡

maintained that the atmosphere acts like the glass in a hot house, because it lets through the light rays of the sun but retains the dark rays from the ground. This idea was

elaborated by Pouillet §; and Langley was by some of his researches led to the view, that ‘the temperature of the earth under direct sunshine, even though our atmosphere were present as now, would probably fall to – 200 °C., if that atmosphere did not possess the

* Extract from a paper presented to the Royal Swedish Academy of Sciences, 11th December 1895. Communicated by the Author.

† “Heat a mode of motion,” 2nd ed. p.405 (Lond.,1865).‡ Mem. de l’Ac. R. d. Sci. de l’Inst. de France, t. vii. 1827.

§ Compress rendus, t. vii. p41 (1838).

Phil. Mag. S. 5. Vol. 41. No. 251. April 1896 S

The CO2 greenhouse effect is not a new idea!

The Precursor: Wladimir I. Vernadsky

”The biosphere is a unique region of the Earth’s crust occupied by life.

There are no stronger chemical forces at the earth surface [...] than living organisms taken in their totality”.

1926

A Century of Successive Milestones

• 1940’s and 1950’s: development of numerical weather prediction (Smagorinski, Charney, von Neumann)

• 1950’s and 1960’s: development of the first comprehensive climate models (Manabe)

• 1957: Sputnik is launched

• 1969: The first picture of the Earth is made from space (Apollo)

A Century of Successive Milestones

The ocean seen as a dynamical component of the Earth System

• The conveyor belt (W. Broecker)• The thermohaline circulation (W. Munk)• Ventilation of the deep ocean (H. Stommel and P.

Rhines)• The biological pump for carbon• Ocean acidification

After Broecker 1991

Change in the strength of the North Atlantic meridional overturning circulation (svds) in a

number of simulations with increases in greenhouse gases

Source: Cubasch et al. 2001

A Century of Successive Milestones

The role of the biosphere in the Earth System

• Identification of the missing CO2 sink as being terrestrial ecosystems (Keeling, Sr and Jr., Tans)

• Importance of vegetation-albedo feedback (e.g., instability of the Sahara by Charney)

• The role of the biosphere in controlling the chemical composition of the natural atmosphere

• The importance of large wildfires

A Century of Successive Milestones

The atmosphere as a ”miner’s canary” of global change

• Increase in the atmospheric concentration of CO2 (D. Keeling)

• Stratospheric ozone depletion and the Antarctic ozone hole (Crutzen, Molina, Rowland)

• The oxidation potential of the atmosphere: the OH radical and tropospheric ozone as a global pollutant (Levy, Weinstock, Crutzen)

A Century of Successive Milestones

The Earth as a nonlinear system

• The Vostock Ice core (Oeschger, Lorius)• The Dansgaard/Oeschger cycles• The CLAW hypothesis (R. Charlson, M. Andreae, et al.)• The Lorenz attractors• The realization of the importance of the carbon cycle (B.

Bolin, R. Revelle)• The iron fertilization (J. Martin)• Multiple vegetation-climate states (Claussen et a.)

The polar ice caps carry the history of the Earth’s atmosphere over millions of years, in the form of bubbles trapped in the ice.

An enigma from the ice…

Antarctic record of temperature, CO2 and CH4

The only place this much carbon can “hide” during the ice ages is in the ocean strong coupling between climate and marine carbon cycle

Methane comes mostly from wetlands strong coupling between climate and terrestrial ecosystems and carbon cycle

… pointing into an uncertain future…

History shows that physical climate, ocean dynamics, terrestrial ecosystems and the carbon cycle are a strongly linked system.

In the last 150 years, we have introduced massive perturbations in some of the forcing variables ---

How will the system respond???

?

Part 2. The Earth as a Complex

System

The Earth System: Coupling the Physical, Biogeochemicaland Human Components

• In nonlinear complex systems, minute actions can cause long term, large scale changes. These changes can be abrupt, devastating, surprising, unmanageable.

From: Steffen et al. 2004

Socio-Economic Driversof Global EnviromentalChange

From: Steffen et al. 2004

Resulting changes in theAtmosphere, Oceans, and Land ...

The Earth is currently operating in a no-analoguestate. In terms of key environmental parameters, the Earth System has recently moved well outside the range of natural variability exhibited over atleast the last half million years. The nature ofchanges now occurring simultaneously in theEarth System, their magnitudes and rates of change are unprecedented.

From: Steffen et al. 2003

Part 3.The new IGBP

IGBP: Role and Objective

• to describe and understand Earth System dynamics,

• focusing on the interactive biological, chemical and physical processes,

• the changes that are occurring in these dynamics,

• and the role of human activities in these changes.

IGBP is an international scientific research programme onglobal change. Its objective is:

• Biological processes play a much stronger role than previously thought in Earth System functioning

• Global change goes beyond climate change. It’s real, it’s happening now and it’s accelerating

• The Earth’s dynamics are characterised by critical thresholds and abrupt changes

• Human activities drive multiple, interacting effects that cascade through the Earth System in complex ways with potentially catastrophic consequences

• The Earth is currently operating in a no-analogue state

The IGBP Synthesis

The New IGBP1999-2003: synthesis project, transition, and restructure

• biogeochemical sciences with relevance to issues of societal concern

• interdisciplinarity and integration

• Earth System context

2004: new questions and structure, with a focus on:

IGBP in the next 10 Years

IGBP will provide scientific knowledge to improve the sustainability of the

living Earth.

IGBP will specifically study the interactions

between biological, physical, and chemical processes, and human systems. It will collaborate with other programmes to provide the knowledge necessary to respond to environmental change.

CHARACTERISTICS OF IGBP II

• More integrative, more interdisciplinary • Global change versus climate change • Strong base in biogeochemical sciences • More emphasis on issues of societal

concern• More emphasis on the regional scale • Strategic partnerships via the Earth

System Science Programme (ESSP)

1. What is the role of the biology in the functioning of the Earth System?

2. How important is chemical and biological complexity in the functioning of the Earth System?

3. How can societies understand, anticipate and adapt to the cascading impacts of multiple interacting stresses?

4. Can human activities inadvertantly trigger abrupt changes in the Earth System, and if so what are the consequences?

Challenges: Research Issues

Research Challenges for theNext Decade

How dangerous is the unintended human experimentwith the functioning of the Earth System?

What are the anthropogenic disturbance regimes and teleperturbations that matter at the Earth System level?

Which are the vital elements and functions of the Earth System that can actually be transformed by human action?

What are the accessible but intolerable (for humans) domains in ’Earth System phase space’?

Part 4.Stewardship of the Earth

System

Stewardship in the Haze

• Human-driven changes are pushing the Earth System into planetary terra incognita

• Management options include merry ignorance, maximum precaution, judicious avoidance and systemic regulations. Earth System models can help choising between these options.

In the NH summer of 2003, extended flooding in Eastern Europe.

In the NH summer of 2004, an unprecedented heat wave in Western Europe.

Hurricane Catarina, 27 March 2004, approaching the coast of Brazil

Expect surprises!

In the SH spring of 2004, an unexpected phenomenon in the South Atlantic.

TRMM

Hurricane Katrina, 28 August 2005

New Orleans, September 2005

In the NH summer of 2005, there was un unprecedented number of intense hurricanes in the North Atlantic.

Fotos: Greenpeace/Daniel Beltra

Foto 17: Seca no lago Curuai.

PERÍODO SECO PORTO VELHO - RIO MADEIRA

0

100

200

300

400

500

600

700

800

900

1000

13-Jun 23-Jun 3-Jul 13-Jul 23-Jul 2-Aug 12-Aug 22-Aug 1-Sep 11-Sep 21-Sep 1-Oct

DIAS

CO

TA

S

Período Seco 1988

Período Seco 1995

Período Seco 2003

Período Seco 2004

Período Seco 2005

Cotas Rio MadeiraPorto Velho In 2005, a very intense

drought struck Amazonia.

Landsat image by INPE

Science for curiosity or for policy makers?

• Has the current research focus distracted the scientific community from addressing more policy relevant questions such as adaptation strategies and limits, reduction of vulnerability, ecosystem management, decarbonization of our energy system, etc.?

• How should decisions be made in a world of scientific uncertainties?

• How can global environmental change research be more relevant to the development needs of the developing nations?

picture Sebastião Salgado 1999

What type of society and nature do people want?

Fragile humans ...

The Future?IPCC Projections2100 AD

2

4

3

5

6

1

0

Glo

bal

Tem

p (°

C)

N.H

. T

emp

(°C

)

0

0.5

1

-0.5

1000 1500 2000

Mann et al (1999) and IPCC 2000

Life exists within a very thin layer of atmosphere!

How fragile is the Earth System?