asked Her Majesty's Government:
What assessment they have made of the latest measurements from the United States National Oceanic and Atmospheric Administration’s Earth System Research Laboratory of the increase of mean carbon dioxide atmospheric concentration at a globally distributed network of marine surface sites; whether, in the light of this information, atmospheric carbon dioxide concentration can be stabilised at 550 parts per million; and what additional measures they will propose at the European Union and United Nations to deal with carbon dioxide and other greenhouse gas emissions. [HL1537]
The latest measurements of atmospheric carbon dioxide concentration show a slightly increasing trend, which will feed through into increased climate forcing and global temperature rise.
The increases in atmospheric CO2 in 2005 and 2006 were high but not exceptional. In 2005 CO2 concentration rose by 2.0 parts per million (± 0.2 ppm) and in 2006 by 2.1 (± 0.2 ppm). These increases were lower than those seen in 2003, at 2.5 ± 0.2 ppm). Between 1958 and 2000 such large annual rises were rare, with only three occurrences in the record.
It is not yet clear whether the above average annual increase in 2005 and 2006 were primarily due to manmade or natural factors. Possible causes include hot dry summers in Europe and drought in Amazonia, with consequent widespread forest fires. It is too early to be confident that the recent trend towards increasing CO2 concentration will continue, though it is considered likely.
Recent analyses, including the Stern review on the economics of climate change, show that, with strong international action to reduce carbon dioxide emissions, stabilisation of atmospheric concentrations at 550 ppm is still achievable. The UK has continued to keep climate change high on its international agenda in 2006. During 2007, the UK will work across all fronts, including the EU, G8 and UN, to inject greater urgency and momentum into the process of driving down global emissions. In addition I refer the noble Lord to the Answer given on 23 January, Official Report, col. WA 215.