Climate scientist Jim Salinger writing in the Herald about California’s record on climate change mitigation policy: read in full here.
One of the largest contributors to sea level rise is the thermal expansion of the oceans. At the moment carbon dioxide levels are about 390 parts per million (ppm).
A study this year showed that, even if emissions stopped once emissions reached 450 ppm, with such a scenario sea level rise because of the warming of the oceans would amount to 20cm by 2100.
Again the maths are inconvenient, amounting to at least 1.6m by 2100. But when we talk of 1 or 2m sea level rise, it continues past 2100.
What is important is that about 60 million people live within a metre of mean sea level, and this is expected to increase to 130 million during this century. Much of this population resides in the major river deltas of South and Southeast Asia.
And in the South Pacific, there are many atoll islands whose maximum height above sea level means they are very likely to be inundated by storm surges during tropical cyclone occurrences.
Therefore, Governor Schwarzenegger’s target of 80 per cent greenhouse gas emission reductions by 2050, and The Climate Change Bill (Scotland) of 42 per cent of a mid-term target by 2020, although bold, are both realistic and necessary to prevent much more than a 2-3C warming of global mean-surface temperature and 1-2m sea level rise by 2100.