Download presentation
Presentation is loading. Please wait.
Published byJasper Lucas Modified over 9 years ago
1
Climate Change: an Introduction ecbi Workshops 2007 Claire N Parker Environmental Policy Consultant european capacity building initiative initiative européenne de renforcement des capacités ecbi for sustained capacity building in support of international climate change negotiations pour un renforcement durable des capacités en appui aux négociations internationales sur les changements climatiques
2
The greenhouse effect in the atmosphere
3
Natural and man-made carbon cycles OCEAN LAND ATMOSPHERE 90 60 5.4 1.7 1.9 Annual transfers,natural and human-made (GtC) 3.3 Source: IPCC
4
CO 2 is major contributor to global warming Current emissions, effect over next 100 years Methane 24% Carbon dioxide 63% Nitrous oxide 10% Others 3%
5
Sources of Greenhouse Gases CO 2 from fossil fuel use (mainly power generation, transport) and land use change (e.g. deforestation) CH 4 (methane) and NO 2 (nitrous oxide) primarily from agriculture
6
Stages in predicting climate change CONCENTRATIONS CO 2, methane, etc. HEATING EFFECT ‘Climate Forcing’. IMPACTS Flooding, food supply, etc. Scenarios from population, energy, economics models Carbon cycle and chemistry models Gas properties Coupled climate models Impacts models CLIMATE CHANGE Temp, rain, sea level, etc. EMISSIONS feedbacks
7
The climate system
8
Strong global warming observed since 1975
9
IPCC’s AR4 2007 Warming is unequivocal… now clearly evident in many aspects of the climate system
10
Signs of climate change Earth surface has warmed by 0.74 C over last century Sea levels rose 20cm last century Glaciers, snow cover and sea ice all declining More heat-waves, droughts and extreme rainfalls More intense cyclones
11
Carbon dioxide in the atmosphere: rapid rise due to human activities
12
CO 2 from fossil-fuel burning: rapid rise since 1950 Source: CDIAC, ORNL
13
Other Greenhouse gases Similar patterns are observed for methane (CH 4 ) and nitrous oxide (NO 2 )
14
AR4: high confidence in radiative forcing data Anthropogeni c is > 10 times that of solar since 1750
15
AR4: models are getting better Models are used to simulate the warming of the last 150 years Their results correlate with anthropogenic + natural warming Natural causes can’t explain what has happened.
16
AR4: observed vs. modelled global climate change
18
What do models predict? AR4: There is now higher confidence in projected patterns of warming, and other regional-scale features, including changes in wind patterns, precipitation and some aspects of extreme events and changes in ice cover
19
This century global temperature likely to be between 1.8 and 4 C above today’s
20
A further warming of about 0.6 C likely from past emissions alone Scale of warming depends on emissions: Low scenario 1.1 – 2.9 C High scenario 2.4 – 6.4 C
21
Geographical patterns of warming Warming expected to be greatest over land and at high northern latitudes
22
Sea levels will rise by 18 to 59 cm by 2100. Additional 10-20 cm or more may come from Greenland and Antarctic ice sheets Snow cover, glaciers and sea ice will continue to decline Rainfall and wind patterns will change Extreme events (rainfall and droughts) more frequent Tropical cyclones more intense Meridional Overturning Circulation in N Atlantic likely to slow down by 25% Other changes in climate will continue
23
The Atlantic Ocean’s Circulation System
24
Changes will continue for centuries, even if GHG concentrations were to be stabilised by 2100
25
Emissions to 2000, and IPCC projections to 2100
26
Towards dangerous levels
27
Past and projected CO 2 emissions from fossil fuel burning IEA World Energy Outlook 2004
28
References & Acknowledgements Climate Change and The Greenhouse Effect, A briefing from the Hadley Centre, Dec 2005- enquiries@metoffice.gov.uk enquiries@metoffice.gov.uk IPCC, Climate Change 2001 Synthesis Report of the Third Assessment Report IPCC, AR4, 2007 DEFRA, UK (Department for Environment, Food and Rural Affairs)
29
Thank You Claire N Parker claire.n.parker@btopenworld.com +44 1763 209 066 +44 7769 66 47 01
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.