"Rising concentrations of greenhouse gases in the earth's atmosphere, resulting from economic and demographic growth since the industrial revolution, are leading to potentially irreversible climate change. Human-induced emissions of greenhouse gases[...] are changing how the atmosphere absorbs energy. The result is known as the enhanced greenhouse effect. Scientific evidence of the Intergovernmental Panel on Climate Change (IPCC) confirms that climate change is already taking place and that most of the warming observed during the last 50 years is attributable to human activities. There is a world-wide consensus of scientists on the problem of climate change and its causes. Scientists further project that the rate of change will be more rapid than previously expected. Projections for climate change, based on current scientific evidence, include the rise in global average surface temperatures by 1.4 to 5.8 degrees Celsius over the next 100 years. This projected rate of warming is the highest in 10,000 years. The rise in temperature is predicted to have strong adverse effects including rising sea levels (between 9 and 88 centimetres), more irregular precipitation patterns, and an increase in extreme weather events like droughts and storms.
"[...] A shift in temperature zones caused by climate change could seriously affect biodiversity and lead to a geographic shift in the occurrence of different species and/or the extinction of species in many locations as the world's ecosystems will not be able to adapt as fast as the climate is changing. Changes in precipitation and more irregular precipitation will mean that water resources in many regions will come under further stress. This will affect both drinking water supplies and irrigation. Floods are further expected to increase water degradation. Moreover, higher maximum temperatures are expected over nearly all land areas. Warm seasons will become dryer in most mid latitude continental interiors, increasing the frequency of droughts and land degradation. This will be particularly serious for areas where land degradation, desertification and droughts are already severe. Sea level rise may also lead to the salinisation and loss of low-lying agricultural land.
"[..] Climate change is expected to have a clear negative impact on agricultural and livestock activities. Climate change will worsen food security and exacerbate hunger. [..] Changes in temperatures and precipitation are also likely to increase the geographic range of vector-borne diseases such as malaria and dengue fever and expose new populations to these diseases. Furthermore, droughts and flooding may increase water associated diseases such as cholera and dysentery, particularly in areas with inadequate sanitary infrastructures. The loss of landmass in coastal areas is likely to lead to increased permanent or temporary displacement of populations. Harbours, offshore infrastructure, coastal urban areas and tourist infrastructures are particularly at risk, while extreme weather events may also damage inland road, rail, and air infrastructure, thereby disrupting vital transportation systems.
"[...] Apart from having direct economic effects on already vulnerable livelihoods in terms of lost endowments and entitlements, the impacts of climate change are also likely to have major macro-economic implications, in both the short and the long-term perspective. Moreover, chronic food insecurity and deteriorating health conditions will put more pressure on national budgets and costs related to potential conflicts due to increasing water scarcity or mass migration may also be expected. Existing poverty and lagging development will amplify the adverse effects of both gradual changes in climatic conditions and extreme weather events, leading to economic losses, including costs for relief and reconstruction efforts that may consume a significant proportion of affected countries' GDP."
Is this quote maybe taken from the script for some Hollywood horror movie? Or is it perhaps taken from an "information" brochure of Greenpeace or the World Wildlife Fund? Or is it perhaps (even) more serious? Surprise, surprise ... yes, it is. It is quoted from a staff working paper, of July 2003, by the European Commission on the policy context relating to a "Directive establishing a scheme for greenhouse gas emission allowance trading within the Community, in respect of the Kyoto Protocol's project based mechanism", which has recently been submitted to the European Parliament.
In a previous life I have been in the business of writing official documents, so I can assure you that the authors of this prose did a marvellous professional job. But is it based on science or fiction? And is it true that the scientific evidence of the Intergovernmental Panel on Climate Change (IPCC) confirms that climate change is already taking place and that most of the warming observed during the last 50 years is attributable to human activities. Well eh .... not exactly. It depends on how you want to read the reports of the IPCC.
IPCC reports are inaccessible for ordinary people, including policymakers. Therefore, the IPCC has popularised its findings and presented a summary for policymakers. But which policymaker cares to read them these days? After all, 17 pages text is too long. This summary has been heavily criticised in many columns on TCS for its slanted presentation of the underlying scientific reports -- and rightly so. But to its credit it must be recognised that it is also pretty frank about the level of scientific knowledge which climatologists believe to possess. In the summary, the word "uncertainty" or an equivalent occurs no fewer than forty times. This is probably unprecedented for such a short document. The most striking illustration of this uncertainty is IPCC's acknowledgement that it knows (very) little about nine out of the twelve mechanisms which are determinant for global warming (see bottom line graph).
Oh yea ... I forgot to tell that there is still another suspect about they know very little, but which has not been included in the graph. It is the most important greenhouse gas: water vapour. As Christopher Essex and Ross McKitrick observe in their recent book ("Taken by Storm, The Troubled Science, Policy and Politics of Global Warming"): "[...] leaving water vapour off the list [...] is like describing the PC software industry and leaving out Microsoft."
What do we make out all of this? There can only be one conclusion: "The science is fatally flawed." Heard that one before? Well ... it is true. It is the translation into everyday language of what the IPCC itself writes in its reports.
