An increasingly large amount of scientific research, published since the IPCC 4th Assessment Report was released in 2007, shows that climate change is occurring right now, and that it is much faster than predicted only two years ago.
The evidence for this statement comes from many areas. The most important ecosystems currently undergoing change include:
-Many physical systems, in widespread sites, are already showing evidence of global warming. Examples include the timing of plant flowering, animal breeding, and lake thawing.
-Higher ocean surface temperatures in Pacific & Atlantic hurricane-formation zones leading to stronger cyclones are definitely related to anthropogenic warming.
-Ocean acidification is occurring quickly, due to CO2 in massive amounts dissolving in salty water. This will have major impacts on marine ecosystems and subsequently food supplies for many countries.
-Probable sea-level rise over the next 100 years will be higher than that calculated in 2007. It will probably increase at least 100cm, based on newly released scientific studies.
-The increased melting of the Greenland ice sheet which began in the summer of 2004 has been definitely related to global warming.
-West Antarctica has melted at an accelerated rate since 1999 and has suffered 10 major ice shelf collapses since then. After an ice shelf collapses there is a rapid and marked acceleration of glacial flows, contributing to sea level increases.
-Sea-ice in the Arctic is disappearing much quicker than previously estimated, and it is almost a given that this area will be ice-free in summer within a few decades.
-Thawing of the boreal permafrost is proceeding much faster than previously calculated, and is expelling a lot more greenhouse gases than expected.
The warming that is now taking place is expected to go on for many centuries, after all human-sourced CO2 escape ceases. This is due to the significant delays that exist in the climate-ocean system, as well as the long half-life of atmospheric carbon dioxide.
Read more at the planet’s greatest climate change blog, or learn more about accelerated sea level rise.