2010 Diary week 17
Global warming, climate change and weather extremes
Book Review
Last week the first part of Global Warming: The Complete Briefing was reviewed. This week Part II points out that “As the great ice-sheet over North America began to melt at the end of the last ice age, the melt water at first drained through the Mississippi into the Gulf of Mexico.” “The retreat of the ice opened up a channel for the water in the region of the St Lawrence river. This influx of fresh water into the north Atlantic reduced its saltiness, thus, cutting off that part of the ocean ‘conveyor belt’.” “Warm water was prevented from flowing northward, resulting in a reversal to much colder conditions.” “The increase in greenhouse gases is by far the largest of the factors which can lead to climate change during the next century.” “The rate of climate change is likely to be larger than the Earth has seen at any time during the past 10,000 years.” “Estimates for the average sea-level rise under the business-as-usual scenario is 12 cm by 2030 and 50 cm by 2100.” “Half of humanity inhabits the coastal zones around the world. Within these, the lowest lying are some of the most fertile and densely populated. To people living in these areas, even a fraction of a metre increase in sea level can add enormously to their problems.”