1. Department for Environment, Food and Rural Affairs
National and Global Cooperation to achieve Low Carbon Societies through Sustainable Development
David A. Warrilow
Department for Environment, Food and Rural Affairs
COP12 Nairobi, 8 November 2006
Good afternoon Ladies and Gentlemen .
In the next 25 minutes I will review the nature of human induced climate change and will consider how far we need to limit climate change.
Hurricane Wilma, courtesy of NOAA

2. Emissions to 1850-2000, and IPCC projections to 210030 20 10
High (SRES A1FI)
Medium-High (A2)
Medium-Low (B2)
Low (SRES B1)
Fossil-fuel emissions (GtC/yr)
Now we turn to the future course of human influence on the climate system.
This figure shows the historic rise in CO2 emissions to 2000 and 4 scenarios of emissions from human activity of carbon dioxide, produced by the IPCC in These show that at least for the next 50 years emissions are likely to continue to grow and in some cases very strongly.

3. How much climate change is too much?
1-2 C Above pre- industrial
Major impacts on ecosystems and species; wide ranging impacts on society, including developing county agriculture.
1.5 – 3 C
Greenland ice-cap starts to melt irreversibly (7 m)
2 - 3 C
Major loss of coral reef ecosystem; considerable species loss; large impacts on agriculture; water resources; health; economies.
General increase in droughts and extreme rainfalls as temperature increases. Up to 88cm sea level rise in next 100 years.
Terrestrial carbon sink becomes a source. C
North Atlantic circulation collapses C
West Antarctic ice sheet collapses (5 m)
The IPCC in its 3rd report indicated that greenhouse gas concentrations would continue to grow through this century leading to temperature increases of between 1.5 and 5.8 C. Such changes will have dramatic effects. We have a large uncertainty range due to the underlying uncertainty about how human societies will develop and how this will affect emissions – without specific climate policies. The other half comes from uncertainty over the sensitivity of the climate system to increasing greenhouse gas concentrations. Assessing impacts adds another level of uncertainty.
But despite these uncertainties we can make some estimates of the risks that a changing climate could bring. The table shown here summarises the types of impacts that we might expect for different levels of climate change. We can see that up to 2C the greatest impacts will be in the natural world – ecosystems and species. Increasing extremes will also be a key factor. Irreversible loss of the Greenland Ice sheet may begin to occur with a global temperature rise of only 1.5 C. This could occur as early as 2040.
Societal impacts tend to become more severe above a 2C rise but this ignores the knock on effects on society of ecosystem disruption. The risks of large scale climate disruption also increase with temperature but identifying trigger points is very difficult. We should note that all of these impact fall within the temperature range predicted by the IPCC.
In considering such threats the EU has proposed that action should be taken to prevent global temperatures rising by more than 2C. We note that this is not risk free and will not avoid all climate change damage – so this is really a rather conservative limit. The EU also noted that a 2C limit would mean keeping CO2 concentrations well below 550 ppm. The level rather depends on climate sensitivity which is rather uncertain and which if anything recent studies suggest could be higher than has been quoted in the 3rd AR.
What would this mean for emissions?

4. © 2005 NatCatSERVICE, Geo Risks Research, Munich Re
Extreme events and economic costs – threat to sustainable evelopment *
$298bn
Economic and insured losses of major natural disasters
© 2005 NatCatSERVICE, Geo Risks Research, Munich Re 20 40 60 80
100
120
1950
1955
1960
1965
1970
1975
1980
1985
1990
1995
2000
$bn
Economic losses (2004 values)
Insured losses (2004 values)
Trend of economic losses
Trend of insured losses
$178 bn *
[Add story line in – climate change is going to matter more and more to people and business as they start to feel it in their pockets]
This slide shows both the economic losses and insured losses from major natural disasters – of which weather related events account for most of the increase.
In 2005 (not shown) the effect of the long hurricane season and Katrina pushed economic losses to an unprecedented provisional cost estimate of $298 bn with insured losses at $70 bn.
In the UK the ABI estimates provisionally that by 2050 the average costs from floods, storms and subsidence will double, and in an extreme year triple, compared to present.
The response will likely be to introduce a red lining system, take adaptation into account, and not to base prices solely on analysis of past experience.
2005

5. Sustainable development issues related to CO2 emissions over the next 100 years
Cumulative CO2 emissions (GtC)
IPCC High Scenario
2030 to 2100
IPCC Low Scenario and stabilisation scenarios 2030 to 2100
IEA projection 2000 to 2030
Historic
This graph shows total accumulated emissions (in GtC) for three main scenarios. The left hand columns shows the IPCC scenarios – the stippled area show the range from the lowest to the highest. The other two are stabilisation scenarios for 450 and 550 ppm. We could also think of these as emission allowances to keep us on track to meet particular stabilisation goals.
The scenarios are made up of historic emissions (to 2000 in dark blue), the International Energy Agency’s base case scenario to 2030 (light blue) and the green the remaining emission to the end of the century.
Key points:
Over the next 30 years without concerted emission reduction action the world could easily emit more CO2 than has been emitted since the industrial revolution (pale blue and deep blue boxes)
In 30 years we will use up more than 60% of our emissions allowance to meet 450 ppm stabilisation – ie twice what we should emit to be on track. Even for a 550 ppm target we will use nearly 40% of our allowance in 30% of the time.
A 550 ppm scenario is unlikely to deliver a 2C limit. Indeed according to the IPCC at stabilisation the temperatures could be between 2 and 5 C higher than today’s values, giving a substantial risk of damaging impacts and climate system disruption.
It would be decidely risk to allow emissions to continue to rise unchecked when we can see that there is a considerable risk of damage and little headroom for manoeuvre. I believe this simple analysis shows that early actions to limit emissions would be essential to reduce the risks of damaging climate change .
But we have a major challenge.

6. Some implications for achieving deep cuts in global emissions
Long-term policy framework – with sustainable development and integral part.
Wide range of issues and large number of actors
Comprehensive range of technologies and policies
Political leadership