Click the title above to hear an 11 minute interview with Dr. Andrew Weaver, lead author of the “future predictions” section of the IPCC report released in February in Paris.
We discuss the role of scientists, and the reliability of the future predictions in the report.
Dr. Weaver says there is some good news: he was directly involved in wrapping up oceans research which indicates a catastrophic failure of the Atlantic Converyor Belt, (often called the “Gulf Stream”) is VERY UNLIKELY to happen this century. There were worries that melting Arctic Ice, and Greenland ice, could reduce salinity in the ocean current that makes the U.S. Northeast, Britain, and Northern Europe habitable. Apparently, despite massive Arctic melts, so far the current research (literally) indicates we shouldn’t be worried about this in the near term.
However, Dr. Weaver concludes we are in for very difficult times, even if we reduce carbon quickly, as we must. And if we cannot decarbonize, our legacy to children and grandchildren will be massive flooding, storms, droughts, and heat.
We discuss the role of Canada’s Arctic. If the vegetative carbon, billions of tons of it, is unfrozen – that is if the new heat melts the permafrost – then massive amounts of Greenhouse Gases will be released. This may be a critical tipping point. Science does not yet know how much of this vegetative matter will become carbon dioxide, and how much methane.
It all depends how much is under water – the swamps and lakes of the North. The previously frozen plant material would decompose without oxygen, and thus become methane – a Greenhouse gas 12 times more powerful than carbon dioxide. Over this huge continental area, a relatively rapid release of methane over a few years, or even a decade, could tip the climate out of control, leading to the ultimate heat described by Sir James Lovelock – the last humans gathered around the Arctic Sea to escape the heat further South.
If the vegetation rots where oxygen if present, then it releases carbon dioxide. Still bad, but not necessarily fatal.
It all depends on how much, how fast, and in what gaseous form this carbon heads into the sky. And science doesn’t know.
Dr. Weaver also describes a just-released study which compares previous IPCC estimates, which have been given every 6 years since 1990 – to what actually happened. The earlier predictions were not only realized, they were conservative, below the heat and other ramifications of climate change that hit us.
There is reason to believe the current IPCC estimates are also low. It was a consensus judgement at the last, involving many countries, including those committed to making money from fossil fuels.
These are my impressions, after the interview – you decide.