Climate change - what is known and how should we act?

Opening session: What is known?

Professor Jan Fridtjof Bernt, President of Norwegian Academy of Science and Letters.

This is the third in altogether seven symposia commemorating the 150th anniversary of The Norwegian Academy of Science and Letters.

The seven symposia are main events in our celebration this year. It is our intention that they should have a twofold effect. The symposia are not only fora for exchange of views and for discussion among the scientists in the fields. They are also intended to highlight the importance of science as a basis for the political decision making and an enlightened public debate on questions on crucial importance to our understanding of the world we are part of and to clarify our options and the means we have to preserve and improve our physical and social environment
In other words, we are not here to celebrate the Academy, we are here to celebrate science and to document its importance.
The topic of this symposium fits the bill. We are going to briefly to discuss topics of controversial and immensely complex nature, where we can not just accept that lack of consensus on our questions or absence of definite certainty on all aspects serve as an excuse for lack of national or global political action.
Waiting till all controversy and disagreement has gone away is simply not an option, an answer not possible, nor desirable from a scientific point of view.

Professor Hans Martin Seip, chair of the Organising Committee:

As already indicated by the president of the Academy, the timing of the seminar is good. The Intergovernmental Panel on Climate Change has worked for several years on the Forth Assessment Report.

The Summary for Policymakers from Working Group I: The physical and scientific basis, was published in the beginning of February. Since then the reports from Working Group II: Climate Change - Impacts, Adaptation and Vunerability, and from Working Group III, Mitigation of Climate Change are also published.

The focus is on what we know. Without anticipating the conclusions of the seminar, I think it is safe to say that we know enough to act.
I have now the pleasure of introducing this afternoon's distinguished speaker, Dr Susan Solomon, co-chair of IPCC Work Group I.

Climate Change - From likely to very likely

Dr. Susan Solomon presented the key findings of IPPC`s Working Group I.

An assessment shows that the average temperature since 1860 has risen by about 0.75°C and the sea level increased in the 20th century by about 0.17 m. WG I finds that it is very likely (90% probability) that the temperature rise since the mid-20th century is caused by manmade increases in the greenhouse gas emissions: mainly CO2, CH4, and N2O.

Compared to pre-industrial times the radiative forcing has increased by 1.6 W/m2. This is the combined effect of the positive forcing from the greenhouse-gasses (GHG), the positive feedback from water vapour, the changes in albedo effects from blackening of snow and decrease in snow- and ice-cover and the negative forcing from atmospheric dust and sulphur particles.

Carbon dioxide is the main GHG. Since 1750 the atmospheric concentration has risen from 280 ppm to 380 ppm, very likely mainly due to anthropogenic emissions from burning fossil fuels. About half of the CO2 from fossil fuels is stored in the atmosphere. Soil, vegetation and the seas absorb the rest.

CO2 in the atmosphere has a long lifetime, 10 - 20% will stay for more than 1000 years. This means that even if we reduced the emissions to 1990-level, the concentration will continue to rise. The consequence is that the mean temperature will continue to rise, the sea level will continue to rise, the glaciers and snow caps will continue to shrink and that the by-effects such as changes in precipitation, the number of severe storms and extreme weather will increase. Humanity will be forced to adapt to changes.

If GHG were kept fixed at current levels, a committed 0.6°C of further warming would happen by 2100. Much more if we keep emittingŠ.1.8°C and up to 4°C or more.

The climate changes will be strongest at high latitudes. For a typical "business as usual" (2090-2099) scenario, global mean warming will be ~2.8 oC; while much of land area warms by ~3.5 oC, and the Arctic warms by as much as ~7 oC.
High latitudes will have increase in precipitation, while some tropical areas will face desertification. To a large extent, dry areas become drier and wet areas become wetter.

Future changes in sea level from expansion of the hot ocean and glacier melt by 2100 could be up to 0.5 m, and up to 1 m  within about 2-3 centuries, depending on how much GHGs are emitted. The potential area loss for a sea level rise of 1m is about 21% of Bangladesh and 12% of Vietnam.  

From right to left: HRH Crown prins Haakon, secretary general Reidun Sirevåg, professor Hans Martin Seip, Dr. Susan Solomon

There are still areas where we need more knowledge, said Dr Solomon, particularly regarding melting of glaciers and changing in storm and hurricanes. The increase in temperature in this century may be sufficient to cause melting of the Greenland icecap although this would take a millennium or more. That would rise the sea level by 5 - 7 meters in addition to the SLR caused by thermal expansion. Should however the ice cap move faster and break up, the rise in sea level will occur much earlier.

WGI does not expect melting of the Antarctic ice cap. Increased precipitation in high latitudes could contribute to build up the snow-cover in Antarctica.

WG I expect that the fraction of CO2 absorbed by soil and the seas will decrease with rising air temperature and that CO2 stored in soil may be released and give a positive feedback.

The coloured lines represent possible different mitigation strategies andt the resulting atmospheric GHG consentraions.

Forget the alternative explanations, said Dr Solomon. Assessment of the forcing from changes in the Suns radiation shows that this is a magnitude smaller than the forcing from the increase in GHG. The ice ages are caused by periodic changes in the earth's orbit.

She commented on several "climate myths":

• Climate has always varied (yes, but a lot of that variability was forced and we know what is causing current change).
• The upper atmosphere isn't warming - it's only the surface (bad data confused us for a while).
• The sun is causing the current changes (the sun hasn't increased in recent decades - neither brightness or cosmic rays or length of the cycle).
• Greenhouse gases are natural (sure, but look at how they've changed)
• Water vapor is the dominant GHG (sure, but it responds to changes in climate - it doesn't force them)
• Good things are happening - longer growing season at mid-latitudes, etc. (good things aren't happening everywhere).

How does IPCC work? - Asessment of research
The Intergovernmental Panel on Climate Change does not conduct research, said Dr Solomon; it works by assessing research done world-wide.
The IPCC formed in 1988 under auspices of the United Nations
Function is to provide assessments of the science of climate change

The IPCC sequence:

• IPCC (1990) Broad overview of climate change science, discussion of uncertainties and evidence for warming.
• IPCC (1995) "The balance of evidence suggests a discernible human influence on global climate."
• IPCC (2001) "Most of the warming of the past 50 years is likely (>66%) to be attributable to human activities."(Third Assessment Report, TAR)
• IPCC (2007) "Warming is unequivocal, and most of the warming of the past 50 years is very likely (90%) due to increases in greenhouse gases." (Assessment Report Four, AR4)

IPCC has three working groups with quite distinct scientific purviews and required expertise.

• WG I - Climate Change: The Physical Science Basis
• WG II - Climate Change: Impacts and Adaptation
• WG III - Mitigation

Work on the Assessment Report 4 started in 1994
Each report is an assessment of the state of understanding based upon peer-reviewed published work. It goes through a demanding process of multiple reviews and revision and re-review:

• Informal zero order draft (ZOD) prepared, comments sought from 6-12 outside experts for each chapter (Oct 2004 - Mar 2005).
• Formal first order draft (FOD) reviewed by about 600 reviewers worldwide (Sept -Nov 2005).
• Formal second order draft (SOD) re-reviewed by about 600 experts worldwide and by dozens of governments (April-May 2006).
• Governments' comments on revised Summary for Policy Makers (Oct-Nov 2006).

WG1 received and carefully considered over 30 000 comments in total (compare this to a typical scientific paper, normally reviewed by 2-3 experts). The assessment is not the view of any single scientist or few scientists. It reflects a broader process.
The breadth of the author teams and the breadth and depth of the review are not achieved by any other process. Thus assessed findings in a final IPCC report are not the views of any individual scientist and reflect a far broader process. 75% of the authors in WG1 IPCC (2007) did not work on the WG1 IPCC (2001) report.
SPM is a Summary for Policy Makers. The process, the chair, and the authors ensure that it is fully consistent with the full report and its science
The full report from WGI and Summary For Policymakers from WGI, WGII and WGIII are available at www.ipcc.ch

oooOooo

Plenary Session in the Norwegian Polytechnic Society

Professor Sissel Rogne, president of The Norwegian Polytechnic Society opened the session, introduced the Chair, Dr. Pål Prestrud, and gave the word to Secretary General Harald Rensvik, Ministry of the Environment who delivered the opening address on behalf of Minister of the Environment, ms Helen Bjørnøy.

The plenery session was held at The National Library:

In the opening address, Mr Rensvik congratulated The Norwegian Academy of Science and Letter on the 150th anniversary and gave a special welcome to Dr. Susan Salomon, Co-chair of IPCC WG I.

We in Norway are very impressed by the work of the IPCC, mr Rensvik said. The assessments of IPCC give the World main points of reference concerning climate change.
As we heard from Dr Solomon earlier today, the Fourth Assessment Report from Working Group I is full of inconvenient and rather frightening truths. It tells us that climate change is a selfreinforcing process, that carbon stored on land and in the sea may be released as the temperature rises.
The report form Working Group II draws a depressing picture of the future. It documents that climate change will affect us all, but that the poorest will be hardest hit.
The seminar addresses two questions: What do we know about climate change and how should we act? The Fourth Assessment Report tells us that we have sufficient knowledge to understand that we have to act.
How should we act? The simple answer should be: Do all we can to reduce greenhouse gas emissions. The time for action is long overdue.
The report delivers a better scientific basis than ever for us politicians to make the right follow-up for our common future, and above all to take the right decisions for the safety of our precious climate.

Panel discussion

The five panelists gave short overviews as introduction to an open dialog with the audience:

• Dr Susan Solomon on the main conclusions from WGI Read more
• Professor Peter Cox on Modelling of the Carbon Cycle Read more
• Dr Hu Tao on Recent Development in China´s Climate Policy Read more
• Professor Christian Azar on the Costs of Mitigation Read more
• Professor Judith Curry on effect of Climate Change on the Formation of Hurricanes Read more

The panel, from left: professor Peter Cox, Dr Hu Tao, professor Christian Azar, professor Judith Curry, Dr Susan Solomon.

In the opening address, professor Sissel Rogne commented on the growing public interest in Climate Change. This was indeed reflected in the number of questions and comments from the audience.

Dinner at The Norwegian Academy of Science and Letters

Session 1

What will happen? Consequences of Climate Change

Chair: Professor Øystein Hov, Norwegian Meterologic Institute, Oslo

From left: Øystein Hov, Helge Drange, Eystein Jansen, Pål Prestrud, Judith Curry, Peter Cox

Arctic climate. ( Drange + Prestrud)
Southern Europe experienced a heat-wave in 2003. It is less known that we had an arctic "heat-wave" in January 2006. At Svalbard the monthly mean temperature was 13 °C above the monthly mean average. At Frantz Josef land the anomaly was 16 °C. This was only possible because sea ice was not present in these regions, combined with quite consistent south and southwesterly winds. In Siberia it was quite different. Here the anomaly was minus 14 °C.
The heat transport across the 70o N is 100 W/m2 annually and more than 150 W/m2 in winter. The heat is transported both by water and by air, with airborne heat as the major contributor. Any changes in the poleward heat transport have the potential to influence the Arctic climate. IPCC estimates a temperature rise of 7.6 °C in the coming 100 years. Loss of snow-cover and sea-ice will reduce the albedo-effect and give a positive feedback.
As the example from January 2006 shows, the Arctic temperature can have large variations geographically. To get a picture of trends you have to use averages, both over several years and over geographic areas.

One of the driving forces is interplay between the Subpolar and the Subtropic gyre.
Observations show that the Thermohaline circulation varies on a multidecadal timescale: warm from 1925 to 1960, cold from 1960 to 1995 and now warm again.
The Arctic is now experiencing some of the most rapid and severe climate change on Earth. Over the next 100 years, climate change is expected to accelerate, contributing to major physical, ecological, social, and economic changes. Changes in the Arctic climate will also affect the rest of the world.
IPCC predicts that the Golf Stream may be reduced, but not by more than 25 % in this century.

Drange lists as main challenges:

• To better understand the dynamics of the variability modes
• Improve feedback-processes in the models
• Quantify the decadal-scale predictability of the system

Prestrud made the following conclusions about possible consequences of climate change in the Arctic:

• Global effects
  -Amplified global warming due to reduced albedo and potentially increased emissions of greenhouse gases from melting permafrost
  -Sea-level rise
  -Increased probability of changes in ocean currents
• Local/regional effects
  -New challenges for Arctic indigenous and local peoples
  -Changes in polar biodiversity and biological productivity
  -Increased accessibility to natural resources and increased possibilities for seaway transport

What will happen to the ice-cap on Greenland and to the sea-ice? ( Prestrud + Jansen)
125 000 years ago most of the ice-cap on Greenland and part of the ice-cap in Antarctic were melted. This resulted in a sea-level rise of 4 - 6 m. Given a world average temperature rise of 3 °C, the Greenland ice-cap may be gone in thousand years, according to AR4.

The main uncertainty does not lie in how fast the ice-cap will melt, but if the ice-cap will move faster into the sea. There is also uncertainty about the mass balance between loss of ice and build up from an increase in precipitation (snowfall).
There are no indications of increased melting of the Antarctic ice-cap, but also here there are indications of more frequent calving, moving the ice from land to sea.
So far the IPCC-estimates on sea-level rise are based on thermal expansion and glacier melting (excluding future rapid dynamical changes in ice flow).

Increase in sea-temperature will reduce the amount of sea-ice, opening the Northern Sea Route for a greater part of the year, but it will also have serious impacts on the living conditions for people, animal life and the vegetation in the Arctic.

Rising temperature will melt the permafrost. This may release methane and CO2 and it will have a major impact on animal life, on living condition for the native population as well as on the growing season for plants and trees.

Precipitation and storm surge ( Curry + Drange)
Several phenomena may contribute to more flood damage. We know that content of water vapour in the atmosphere will increase with increasing air, land and sea temperature. Changes in air circulation will however give increased precipitation at high latitudes and less precipitation in areas that already are dry.

The sea-level rise since 1750 is 14 cm. During this century the sea-level may rise by half a meter. In many places this is serious, but the main short time threat is heavy wind in conduction with low air pressure, leading to storm surges and heavy rain. In Norway land rise will partly compensate for SLR

Hurricanes can form when the sea-surface temperature is above 26.5 °C. Major hurricanes seem to require at least 28.5 °C. Strong wind-shear, differences in wind speed with height, will hinder the formation of a hurricane.

Tropical hurricanes can have devastating effect if they have landfall in a low-laying and densely populated area, like in Bangladesh. On Nov. 17th, 1970, a tropical cyclone crossed the coast of Bangladesh. A 12-15 ft storm surge, at high tide, drowned 300,000 -500,000 people. In 30 years the population has doubled, and 1/3 of Bangladesh is less then 1 m above sea-level!

The disastrous damage that may occur was also illustrated when the hurricane Katrina hit New Orleans. This same storm moved across the Atlantic and hit Bergen, giving a storm surge and 100 to 150 mm of rain in 12 hours.

The sea-temperatures in the Golf and the Pacific are traditionally high. An increase in global temperature is expected to have small influence on storm formation here. In the Atlantic, however the situation is different. Studies show that the recent rise in sea-temperature has not given an increase in the total number of storms in the Atlantic, but a significant rise the number of heavy storms. Although effects of global warming on the intensity of tropical storms and hurricanes are highly controversial, we have to prepare for more storm surges, heavy precipitation and strong winds. Protection may be possible in the rich countries, but what about the poor?
In Bergen one is discussing ways to bloc the sea to avoid the effects of storm surges.

What can we learn from the past? ( Jansen)
The size of projected temperature changes for this century is similar to the glacial impacts. The temperature at the Last Glacial Maximum (LGM) was about 4 °C lower than the mean pre-industrial temperature. Comparison of observed data with data calculated by the models we use for predicting the future climate, shows that the models correspond well with the findings from the glacial time.
Astronomical calculations of the of the Earth's orbit (eccentricity, axial tilt, and precession) tell that we should not expect a new ice age in the coming 20 000 - 30 000 years. The same model tells that we should expect a warm period at high latitudes 6000 years back from the present, solely due to incoming solar radiation

From various temperature reconstructions IPCC concludes:
It is very likely that the last 50 years are the warmest in the past 500 years and likely that they are the warmest in the past 1300 years.
Some of the conclusions given by Jansen are:

• Our understanding of climate forcing is consistent with LGM and the last 1000 years climate change
• Climate models simulate many aspects of the observed changes reasonably well when forced with known forcing factors
• Warm periods of the Holocene had different origin and geographic extent than the ongoing warming
• Future climate change will be large compared with natural changes of the last millennia
• Rates of change of forcing and expected responses are unique now, even on geological time scales.

Carbon cycle feedback (Cox)

Session II

How can we reduce Climate Change?

Chair: Dr. Gunnar Eskeland, Cicero

From left: Dr Gunnar Eskeland, professor Christian Azar, Dr. Perry Barker, Dr Kristin Aunan, Dr. Hu Tao.

Can we still avoid dramatic climate change?
Yes, said Professor Christian Azar, we can avoid dramatic climate change, but that requires tough political decisions. So far we are going in the wrong direction.

Professor Azar shoved an energy scenario towards 350 ppm. CO2 from as well fossil fuels as from biomass is sequestered and solar hydrogen plays a prominent role. His conclusions were:

• Tough challenge
• Technically feasible
• Economically feasible
• But trends go in the wrong direction
• Policy measures needed, but is there enough political will?

T he economic costs and benefits of avoiding dangerous climate change. ( Azar + Barker)
Greenhouse gasses are intrinsic to economic development, said director Terry Barker. Much of historical growth has come from industrialised countries' use of coal, oil and gas - they are responsible for 70% of the extra GHG stock in the atmosphere. The
CO2/GDP ratio has started falling, but not fast enough

Over-use of common resources, combined with global economic growth leads to problems: climate change, loss of biodiversity and to pollution of air, land and water
These problems are challenging because action requires international agreement between sovereign states.
The effects are uncertain and diffused, and they are difficult to measure. The costs of reduction (of over-use) are immediate and concentrated, often on groups with strong lobbying power (fossil fuel industries). On the other hand, the benefits of reduction are widespread but often small and on other countries and future generations

The costs of mitigation must be seen in connection with the costs and the benefits of climate change, the cost of adaptation and the benefits of mitigation. Climate change will give more floods and more droughts. This necessitates flood defences and irrigation. Mitigation may reduce these consequences, reduce the adaptation costs and also give some co-benefits such as less air- and water pollution

The costs of mitigation are usually measured by difference from baseline GDP. The cost of mitigation depends on the target, said professor Azar. If we choose to stabilise on 350 ppm, which is less than today's level, it could cost about 18 trillion USD. If we set the target at 550 ppm the cost is estimated to two trillion USD. However, if we compare the mitigation cost to the expected rise in global GDP, the costs to stabilise the atmosphere are small.

The Stern Review has assessments of costs of climate change: 5 to 20% of global GDP) and costs of mitigation: -1 to +3.5% of GDP). The costs of doing nothing far outweigh costs of mitigation: therefore act urgently, said Dr. Barker!
The target is to avoid dangerous climate change. What is dangerous is however an ethical and political issue.

The Stern reports concludes that "The current evidence suggests aiming for stabilisation somewhere within the range 450 - 550ppm CO2equivalents. Anything higher would substantially increase risks of very harmful impacts." (550 CO2eq is equivalent to 450 CO2 only).
There is strong evidence from the modelling that induced technological change (ITC) becomes more important in reducing costs for more stringent targets. However, general technological change alone is unlikely to work. Improvements in energy efficiency are offset in their effects on emissions by higher growth in exports, incomes and energy demand. Therefore a rising real carbon price is required.
Carbon-price policies are most efficient if all sectors of the economy are covered.

Avoiding dangerous carbon cycle climate change is feasible and, with well-designed policies, beneficial to the global economy and development, but with risk for policy mismanagement.

What is happening in China? ( Kristin Aunan + Hu Tao)
Dr Kristin Aunan reported in her presentation: Air Pollution and global warming - measures of co-benefits in China:
China is soon going to pass the USA as the largest emitter of GHGs although the per capita emissions are still low. However, air pollution abatement is the issue in China, not GHG mitigation. Today cities in China are among the most polluted globally. Unfortunately, China has not been able to meet critical 10th five year plan targets for air pollution, although simple actions like washing and briquetting coal can give significant reductions in pollution.

There are several climate-change and air-pollution links:

• Source link: CO2 and the main air pollutants to a large extent have the same sources
• Air pollutants, especially tropospheric ozone and particles, play an important role in the climate system
• Chemistry: Some air pollutants affect the lifetimes of GHGs (e.g. increased CO may increase the lifetime of CH4)

Many measures may therefore reduce both air pollution and CO2 emissions. A range of current Chinese laws and regulations have the potential of achieving such effects. Dr. Aunan's conclusions were:

• A range of present Chinese policies has the potential of leading to combined air quality improvements and CO2 reductions, but stronger enforcement is needed
• Clean coal technologies and energy efficiency improvements are cost-efficient options for co-control of air pollution and CO2 emissions
• Policies promoting clean household fuels in China may substantially reduce population exposure to particulate air pollution and may also be beneficial for regional and global climate

Dr Hu Tao reported in his presentation: Recent developments in China's climate policy: on what China has done, what China is doing and what China is planning to do.
China has signed the Kyoto Protocol. Domestically China has passed the Energy Saving Law and Renewable Energy Law.
Action is taken through:

• Energy efficiency programs
• Economic structure adjustments
• Low carbon and new and renewable energy developments
• Plantations for carbon sequestration
• Population control with 0.5 % annual growth rate

China's carbon emission per capita is less than the world average and only about 1/3 of that in the OECD countries (data for 2004). Energy consumption per unit of GDP is now on par with the US and other industrialised countries.

The 11th Five Year Plan (2006 - 2010) requires 20% energy- and GHG intensity reduction, 10% SOx reduction, 1.8 % increase in forest territory.

China is working on an ambitious National Climate Plan. The plan was to be official by April 30th, but has been postponed.
In addition to the reduction in energy intensity, targets include:

• By 2010 renewable energy shall account for 10% of total energy and nuclear energy for 4% of the total
• By 2010 N2O shall be at the same level of 2005
• Control paddy rice and animal methane emissions
• 50 million ton of carbon sequestration increasing during 2005-2010

There are also discussions of long-term targets in China, e.g. emission targets for 2060, but in the report we conclude that we do not know what is going to happen in the post-Kyoto negotiations. We just set up targets that are realistic to achieve.
Dr Hu Tao pointed out that China in the future might refuse to import energy intensive industries from industrial countries.
China will reduce its emissions: in production through higher energy efficiency, in consumption by at the same time improve quality of life and reduce the consumption level. One action is to try to avoid the same high consumption level as in Norway. That the Earth could not support.
We need to have a market system to achieve reduced energy consumption, said Dr. Hu. It is a challenge that increasing energy prices will hit the poor people. Therefore the Peoples Congress has refused to introduce fuel tax. In the future we have to balance subsidies and prices.

How should we act?

Is mitigation possible? Some political considerations.
Final discussion, moderator: Dr. Gunnar Eskeland

Participants in the discussions of the individual presentations and in final discussion.

The final discussion addressed the feasibility of getting the necessary national and international political support for mitigation programs.
How can we defend a given target? What is special about the EU two-degree limit to average global temperature rise? What is special about the 550 ppm limit on GHG which is the upper bound in The Stern Report?
Will it be necessary to discuss overshoot, to accept that we will exceed emission targets set to achieve equilibrium, and then later return?

Calculations show that the net cost of mitigation is modest in comparison with the expected economic growth. Traditional cost/benefit analyses give the result that we should not do too much, that we should not take the costs to stabilise at 350 or 450 ppm.
There is however a paradox that many scientists warn of catastrophic consequences of not doing anything. Almost all economic calculations are based on the assumption that the global GDP will continue to grow, regardless of whether we mitigate or not, and that people are going to be much, much better off than today.
How can we combine this with the notion that the consequences of climate change can be catastrophic and devastatous for all species and indeed life on earth?
Does this mean that we are in deep trouble and that should take drastic action immediately. Does the world need new leaders and a new philosophy?
The costs of doing things very suddenly can, in economic terms, be extremely costly.
On the other hand is it obviously a puzzle that the western societies have become much richer materially, but not become much happier. It is therefore not necessarily true that a change in lifestyle will make people less happy.
It is important to remember that damage cost is calculated to rebuilding, not to restoring. The official costs for rebuilding New Orleans will not cover the costs for returning New Orleans to what it was before the hurricane. If we contemplate protecting Venice or returning Venice from a hundred-year storm to what it was, we will find that the costs for restoring would be enormously high.
Dr Eskeland pointed out that the belief that we can do a lot to avoid dramatic climate change rests on a few spesialists. All our societies are political animals. We need to have people on our side. The mitigation policies will be weak if they are not supported by evidence. He challenged the scientists: "You got to be there. Your message got to be credible. It is dangerous to have a fight between good scientists, issue by issue.
It is important to have mitigation policies that are not too aggressive, and that we know can be sustained over time. So for all the proposal we are making, it is important to know that we can sustain them and strengthen them over time".

Professor Seip, in his final remarks, pointed to earlier mitigation programs, for example the reductions in sulphur emissions in the US, which have turned out to be much cheaper than anyone had expected. He also quoted what Henry David Thoreau wrote more than 150 years ago:
Most of the luxuries and much of the comforts of life are not only not indispensable but positive hindrances to the elevation of mankind .

List of presentations:
Presentations are available for download at: www.dnva.no

• Dr Susan Solomon, Senior Scientist NOAA, Boulder Colorado USA, Co-Chair of IPCC, Working Group I:
  IPCC's Fourth Assessment Report - Main Findings of Working Group I
• Professor Helge Drange, Institute of Geophysics, University of Bergen, Norway:
  Present and future climate change in Northern Europe.
• Professor Eystein Jansen, Bjerknes Centre for Climate Research and Department of Earth Science, University of Bergen, Norway:
  Natural climate variations - what do we know and what is their relevance for future climate change?
• Director, Dr. Pål Prestrud, Center for International Climate and Environmental Research, Oslo Norway:
  Climate change in the Arctic.
• Professor Judith Curry, School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA:
  An updated overview of the state-of-the-art with respect to hurricanes and climate change.
• Professor Peter Cox, School of Engineering, Computer Science and Mathematics, University of Exeter, UK:
  Modelling with emphasis on carbon cycling.
• Professor Christian Azar, Physics and Engineering Physics, Chalmers University of Technology, Gothenburg, Sweden:
  Can we still avoid dramatic climate change?
• Director, Dr. Terry Barker, Cambridge Centre for Climate Change Mitigation Research, Department of Land Economy, University of Cambridge, UK:
• The economic costs and benefits of avoiding dangerous climate change.
• Dr. Kristin Aunan, Center for International Climate and Environmental Research, Oslo Norway:
  Air pollution and global warming - measures with co-benefits in China.
• Dr. Hu Tao, Policy Research Center for Environement and Economy at State Environmental Protection Administration (SEPA) Bejiing, China:
  Recent development in China's climate policy.

Further reading:

• http://www.ipcc.ch/
• http://www.cicero.uio.no/
• http://en.wikipedia.org/wiki/Global_Warming
• Politics and Law - Energy and Environment in the far north
• Nordområdene - et skjebnespørsmål for Norge!
• Klimaproblemene - hva bør Norge gjøre?

Bilder: Nils Chr. Tømmeraas

Referent: Nils Chr. Tømmeraas.