CLIMATE CHANGE: THE SCIENCE, IMPACTS AND SOLUTIONS

By Y. GAMAU

CONTENTS 1 CLIMATE CHANGE MATTERS TURNING UP THE HEAT WHY IS THE PRESENT RAPID WARMING HAPPENING? THE IMPORTANCE OF DELAYED CLIMATE RESPONSES OBSERVED IMPACTS TRENDS IN HUMAN VULNERABILITY PROJECTIONS OF FUTURE CLIMATE CHANGE FACING THE CHALLENGE CONCLUSION ENDNOTES 2 LEARNING FROM THE PAST PROXY DATA: CLUES FROM THE PAST THE RECORD OF THE ICE AGES THE CAUSES OF PAST CLIMATE CHANGE VARIATIONS IN THE EARTH’S ORBIT ROLE OF GREENHOUSE GASES IN AMPLIFYING CLIMATE CHANGES VARIATIONS IN SOLAR OUTPUT VOLCANOES, COSMIC COLLISIONS AND AEROSOLS RAPID CLIMATE CHANGES IN THE PAST THE LAST 10 000 YEARS CONCLUSIONS FROM THE PAST RECORD 3 PROJECTING THE FUTURE THE NEED FOR, AND NATURE OF, FORESIGHT PREDICTIONS, SCENARIOS AND PROJECTIONS THE EMISSIONS SCENARIOS USED BY THE IPCC PROJECTIONS OF SOCIO-ECONOMIC FUTURES FORECASTING THE WEATHER WHY CLIMATE PROJECTIONS ARE DIFFERENT HOW GOOD ARE CLIMATE MODELS? THE STATE OF CLIMATE PROJECTIONS 4 UNCERTAINTY IS INEVITABLE, BUT RISK IS CERTAIN DESPITE UNCERTAINTIES, DECISIONS HAVE TO BE MADE UNCERTAINTY IN CLIMATE CHANGE PROJECTIONS FROM POLARISATION TO PROBABILITY AND RISK ESTIMATING RISK UNCERTAINTY AND THE ROLE OF SCEPTICS APPLICATION OF THE ‘PRECAUTIONARY PRINCIPLE’ 5 WHAT CLIMATE CHANGES ARE LIKELY? PROJECTED CLIMATE CHANGES SURFACE WARMING REGIONAL WARMINGS PRECIPITATION AND EVAPORATION EXTREME EVENTS SEA-LEVEL RISE THRESHOLDS AND ABRUPT OR IRREVERSIBLE CHANGES SCENARIOS IN A NUTSHELL 6 IMPACTS: WHY BE CONCERNED? CLIMATE CHANGE IMPACTS – REASONS FOR CONCERN THRESHOLDS AND ABRUPT CHANGES RISKS TO UNIQUE AND THREATENED SYSTEMS RISKS FROM EXTREME CLIMATE EVENTS DISTRIBUTION OF IMPACTS AGGREGATE IMPACTS WAKING THE SLEEPING GIANTS EFFECTS OF A BREAKDOWN IN THE OCEAN CIRCULATION RAPID SEA-LEVEL RISE FROM MELTING ICE SHEETS RUNAWAY CARBON DYNAMICS SECURITY IMPLICATIONS STABILISATION OF GREENHOUSE GAS CONCENTRATIONS GROWING REASONS FOR CONCERN 7 ADAPTATION: LIVING WITH CLIMATE CHANGE ADAPTATION CONCEPTS AND STRATEGIES COSTS AND BENE?TS OF ADAPTATION IMPLEMENTATION EFFECTS OF DIFFERENT RATES OF CLIMATIC CHANGE EQUITY ISSUES IN ADAPTATION ENHANCING ADAPTIVE CAPACITY 8 MITIGATION: LIMITING CLIMATE CHANGE WHY MITIGATION IS NECESSARY TARGETS: HOW MUCH MITIGATION IS NEEDED? WHERE WE ARE NOW HOW DIF?CULT IS MITIGATION? THE LOOMING PEAK IN OIL PRODUCTION MITIGATION OPTIONS INCREASED ENERGY EF?CIENCY CHANGES IN INFRASTRUCTURE AND BEHAVIOUR FUEL SUBSTITUTION NUCLEAR POWER HYDROPOWER SOLAR ENERGY WIND POWER BIOMASS ENERGY TIDAL AND WAVE ENERGY GEOTHERMAL POWER THE HYDROGEN ECONOMY CARBON CAPTURE AND SEQUESTRATION LAND-BASED CARBON SINKS GEOENGINEERING POSSIBILITIES TECHNOLOGICAL INNOVATION: ATTITUDE IS VITAL THE ROAD TO EFFECTIVE MITIGATION 9 CLIMATE CHANGE IN CONTEXT SURFACE AIR POLLUTION AND CLIMATE CHANGE STRATOSPHERIC OZONE DEPLETION LAND-USE CHANGE, BIODIVERSITY, AGRICULTURE AND FORESTRY LAND DEGRADATION AND DESERTI?CATION FRESHWATER SUPPLY POPULATION GROWTH SYNERGIES AND TRADE-OFFS INTEGRATION, SUSTAINABLE DEVELOPMENT AND EQUITY POSTSCRIPT: CONNECTIONS BETWEEN ECONOMIC AND CLIMATE CRISES 10 THE POLITICS OF GREENHOUSE IS THE SCIENCE CREDIBLE? WHAT ABOUT THE UNCERTAINTY? HOW REALISTIC ARE THE SCENARIOS? CHOOSING GLOBAL AND LOCAL EMISSIONS TARGETS HOW URGENTLY DO WE NEED TO ACT? HOW MUCH WILL REDUCING EMISSIONS COST? MEETING TARGETS MOST EF?CIENTLY INTERNATIONAL EQUITY: WHAT IS FAIR? THE IMPORTANCE OF EQUITY WITHIN COUNTRIES EQUITY BETWEEN GENERATIONS THE ROLE OF GOVERNMENTS AND NGOS WHAT ROLE SHOULD BUSINESS TAKE? THE ROLE OF STATE AND LOCAL GOVERNMENTS SO WHAT ARE THE POLITICS OF GREENHOUSE? 11 INTERNATIONAL CONCERN AND NATIONAL INTERESTS A BRIEF HISTORY THE KYOTO PROTOCOL NATIONAL INTERESTS AND CLIMATE CHANGE AFRICAN NATIONS AUSTRALIA AND NEW ZEALAND CHINA EUROPEAN UNION INDIA, PAKISTAN AND BANGLADESH LATIN AMERICA THE RUSSIAN FEDERATION SMALL ISLAND STATES UNITED STATES OF AMERICA THE COMMON INTEREST IN GLOBAL SOLUTIONS 12 ACCEPTING THE CHALLENGE LOOKING BEYOND THE KYOTO PROTOCOL ADDRESSING THE KEY ISSUES