The three working groups of the IPCC has given three reports on the impact of global warming and the result, climate change. Since the IPCC received the Nobel Prize a few months ago, together with Al Gore, the scientists involved seemed to have taken their gloves off. They are much less sensitive to Governmental Changes on the language in these important reports - and also much less sensitive to the sources of grants for continuing their studies. This is a good thing. After reading and studying all the reports, the language in this synthesis report really has changed. It is a wake up call for those that have not woken up yet. One of the most defocussing arguments over the past number of years, was if human activity caused global warming. The results of that debate is in and there is no doubt any longer. This report contains a section whereby they detail the effects in a scant 18 years away, 2020. Things of course will not suddenly start in 2020 but we are already in a global warming cycle.
Draft synthesis report from the bbc's website
Here are a few highlights focused on island environments for those that don't feel like taking the time to read this. I would however urge you to take the time and read, digest and understand this material.
Causes of change
Changes in atmospheric concentrations of greenhouse gases (GHGs) and aerosols, land-cover and solar radiation alter the energy balance of the climate system.
There is very high confidence that the net effect of human activities since 1750 has been one of warming.
Examples of some projected regional impacts
Small Islands
• Sea-level rise is expected to exacerbate inundation, storm surge, erosion and other coastal hazards, thus threatening vital
infrastructure, settlements and facilities that support the livelihood of island communities;
• Deterioration in coastal conditions, for example through erosion of beaches and coral bleaching is expected to affect local
resources;
• By mid-century, climate change is expected to reduce water resources in many small islands, e.g., in the Caribbean and Pacific, to the point where they become insufficient to meet demand during low-rainfall periods.
• With higher temperatures, increased invasion by non-native species is expected to occur, particularly on mid- and high latitude islands.
Latin America
• By mid century, increases in temperature and associated decreases in soil water are projected to lead to gradual
replacement of tropical forest by savanna in eastern Amazonia. Semi-arid vegetation will tend to be replaced by aridland
vegetation.
• There is a risk of significant biodiversity loss through species extinction in many areas of tropical Latin America;
• Productivity of some important crops is projected to decrease and livestock productivity to decline, with adverse
consequences for food security. In temperate zones soybean yields are projected to increase. Overall, the number of
people at risk of hunger is projected to increase (TS; medium confidence).
• Changes in precipitation patterns and the disappearance of glaciers are projected to significantly affect water availability
for human consumption, agriculture and energy generation.
Human influences have:
• very likely contributed to sea level rise during the latter half of the 20th century
• likely contributed to changes in wind patterns, affecting extra-tropical storm tracks and temperature patterns
• likely increased temperatures of extreme hot nights, cold nights and cold days
• more likely than not increased risk of heat waves, area affected by drought since the 1970s and frequency of
heavy precipitation events.
Projected climate change and its impacts
There is high agreement and much evidence that with current climate change mitigation policies and related sustainable development practices, global GHG emissions will continue to grow over the next few decades.
Regional-scale changes include:
• warming greatest over land and at most high northern latitudes and least over Southern Ocean and parts of
the North Atlantic Ocean, continuing recent observed trends (Figure SPM.6) in contraction of snow cover
area, increases in thaw depth over most permafrost regions, and decrease in sea ice extent; in some
projections using SRES scenarios, Arctic late-summer sea ice disappears almost entirely by the latter part of the 21st century
• very likely increase in frequency of hot extremes, heat waves, and heavy precipitation
• likely increase in tropical cyclone intensity; less confidence in global decrease of tropical cyclone numbers
• poleward shift of extra-tropical storm tracks with consequent changes in wind, precipitation, and temperature patterns
• very likely precipitation increases in high latitudes and likely decreases in most subtropical land regions, continuing observed recent trends
Disagreements over the Science Behind Global Climate Change
