3 Oct 2002 Creative Research Enterprises’ PresentationPolytechnic University of Puerto Rico

Slide 1

HUMAN ACTIVITIES AND GLOBAL CHANGE

In olden days we had to watch our activities for only temporary local scale pollution.

Now we, human being, have become a force that may produce lasting change on global scale!

Agenda:

•Putting perturber and the perturbed in perspective

•Mechanisms for human activity - lasting global change connection

•Our recent magnificent achievement

•More difficult task ahead

•Concluding remarks

3 Oct 2002 Creative Research Enterprises’ PresentationPolytechnic University of Puerto Rico

Slide 2

HUMAN BEINGS ARE MINISCULE RELATIVE TO THE EARTH SYSTEM

Earth ~ 6x1024 kg

Ocean ~ 1.4x1021

Atmosphere ~ 5.3x1018

Biosphere ~ 5.6x1016

Humans ~ 6 x1011

Masses (kg) of highly significant trace gasesCO2 ~ 1.6x1015 ; O3 ~ 8.7x1012 ; N2O ~ 1.5x1012; CH4 ~ 5.2x1012

3 Oct 2002 Creative Research Enterprises’ PresentationPolytechnic University of Puerto Rico

Slide 3

THE TRACE GASES (O3, CO2, CH4, N2O) HAVE VERY IMPORTANT ROLES

3 Oct 2002 Creative Research Enterprises’ PresentationPolytechnic University of Puerto Rico

Slide 4

ABSORPTION OF SOLAR ENERGY BY O2 AND O3 IS VERY IMPORTANT FOR THE BIOSPHERE

It protects the biosphere from harmful ultra violet

3 Oct 2002 Creative Research Enterprises’ PresentationPolytechnic University of Puerto Rico

Slide 5

THE TRACE GASES (O3, CO2, CH4, N2O) SERVE AS GREENHOUSE GASES AND KEEP THE EARTH

LIVABLE

3 Oct 2002 Creative Research Enterprises’ PresentationPolytechnic University of Puerto Rico

Slide 6

HUMAN ACTIVITIES - GLOBAL CHANGE CONNECTION IS NOW UNDERSTANDABLE

Despite being miniscule (10-13) relative to the Earth system, human can cause lasting and global change if our activities:

• increase greenhouse gases (that have long lifetimes)

• change the stratospheric ozone (that provides UV shield over biosphere)

Following slides show that both are not only possible but are either happening or have happened

3 Oct 2002 Creative Research Enterprises’ PresentationPolytechnic University of Puerto Rico

Slide 7

3 Oct 2002 Creative Research Enterprises’ PresentationPolytechnic University of Puerto Rico

Slide 8

CO2 IS BIOSPHERICALLY REGULATED AND IS PRONE TO ANTHROPOGENIC PERTURBATION

Amount stored in: billions of tons1. Atmosphere 2,3002. Oceans 130,0003. Earth (mostly in fossil fuels) 40,000Yearly flux billions of tons/yr 1.From biosphere to atmosphere (respiration

and decay of organic material) 602. From atmosphere to biosphere (photosynthesis) 603. From oceans to atmosphere 1004. From atmosphere to oceans 1005. Into atmosphere from Earth’s interior

(volcanoes, hot springs) 0.16. Into new fossils within earth <0.17. Into atmosphere through human’s

combustion of fuels 68. Into atmosphere from newly cultivated soil 2

3 Oct 2002 Creative Research Enterprises’ PresentationPolytechnic University of Puerto Rico

Slide 9

ATMOSPHERIC N2O IS SIMILAR TO CO2

Estimated Sources of N2O

(TgN/yr)

3 Oct 2002 Creative Research Enterprises’ PresentationPolytechnic University of Puerto Rico

Slide 10

STRATOSPHERIC OZONE IS PHOTOCHEMICAL IN ORIGIN BUT IS REGULATED BY GASES OF

ANTHROPOGENIC ORIGIN

Pristine pre-biological Atmosphere

O2 + solar UV(<200nm) O + O

O + O2 + M O3 +M

O3 + UV (200-300 nm) O + O*

O3 + O O2 + O2

Pre- & post-industrial present times

O* + H2O OH + OH

O* + N2O NO + NO

NO + O3 NO2 + O2

NO2 + O NO + O2

O + O3 O2 + O2 (Catalytic cycle)

3 Oct 2002 Creative Research Enterprises’ PresentationPolytechnic University of Puerto Rico

Slide 11

MORE EXAMPLES OF REGULATION BY GASES OF ANTHROPOGENIC ORIGIN

Cycle 2:

Cl + O3 ClO + O2

OH + O3 HO2 + O2

ClO + HO2 HOCl + OHHOCl + solar radiation OH + ClNet: 2O3 3O2

Cycle 3:Cl + O3 ClO + O2

ClO + NO Cl + NO2

NO2 + O NO + O2

Net: O + O3 O2 + O2

Cycle termination:ClO + NO2 ClONO2; HO2+ Cl HCl + O2

CFC + solar UV Cl

CH3Cl + solar UV CH3 + Cl

Cycle 1:

Cl + O3 ClO + O2

ClO + O Cl + O2

3 Oct 2002 Creative Research Enterprises’ PresentationPolytechnic University of Puerto Rico

Slide 12

MORE COMPLEX REACTIONS LEAD TO OZONE HOLE IN THE SPRING TIME POLAR REGIONS

3 Oct 2002 Creative Research Enterprises’ PresentationPolytechnic University of Puerto Rico

Slide 13

OUR RESPONSE TO OZONE HOLE WAS MAGNI-FICIENT: WHAT ABOUT GLOBAL WARMING?

Year

3 Oct 2002 Creative Research Enterprises’ PresentationPolytechnic University of Puerto Rico

Slide 14

GLOBAL WARMING HAS THE POTENTIAL TO PRODUCE SERIOUS CONCEQUENCES

3 Oct 2002 Creative Research Enterprises’ PresentationPolytechnic University of Puerto Rico

Slide 15

MANAGING GREENHOUSE GAS EMISSION IS MUCH MORE DIFFICULT

• climate-friendly technologies, commonly referred (Technology Cooperation)

• practices that reduce greenhouse gas emissions and increase carbon sinks (Land Use and Forestry management changes)

Both affect energy that is so fundamental to our society—it powers our homes, businesses, and industries (“bread and butter situation)

No wonder implementation of the Kyoto Protocol to control greenhouse gas emission is proving so much more difficult than the Montreal agreement

3 Oct 2002 Creative Research Enterprises’ PresentationPolytechnic University of Puerto Rico

Slide 16

CONCLUDING REMARK

• Setting aside current fierce debate over seriousness of global warming, sooner or later we have to face the challenge of doing without fossil fuels

• The hope is that we will do it sooner rather than later and thereby be prepared for “what if global warming turned out to be serious?”

At current consumption rate (~4.7 Btons/yr), it will last about 230yrs. Then what?