Where I ended up after a series of happenings as described below, is concluding that we need a paradigm shift in our climate change aspirations. Instead of trying to limit warming to a point where we can avoid dangerous climate change, we need to recognize that we’ve already gone too far, that the climate is already dangerous, so we should aim to ratchet down GHG concentrations in the atmosphere to attain a safe climate.
1. Germans look to 7.4 trillion tons of fake snow to save the West Antarctic Ice Sheet
This assessment involves 84 scientists from more than 40 institutions, and combines data from 24 satellite surveys. It follows in the footsteps of the first IMBIE (Ice Sheet Mass Balance Inter-comparison Exercise) conducted in 2012, and paints a particularly grim picture of the years between then and 2017. Continue reading Antarctic ice loss rates have tripled since 2012→
a revised worst-case sea-level rise scenario of 2.5 metres by 2100, 5.5 metres by 2150 and 9.7 metres by 2200. It says sea level science has “advanced significantly over the last few years, especially (for) land-based ice sheets in Greenland and Antarctica under global warming”, and hence the “correspondingly larger range of possible 21st century rise in sea level than previously thought”.
The government has produced the latest State of the Environment Report 2016 which happens every five years. I’ve browsed the report and can say that it has some magnificent photographs.
According to the ABS Australia’s population will be between 36.8 million and 48.3 million in 2066 as against 24 million now. The report says that the key drivers of environmental change are population growth and economic activity.
In the post Scoping long-term sea level rise I indicated the possibility of 25 metres (±5) of SLR with emissions of 380 (360-400)ppm and a temperature variance of 2.7 to 3.7°C. The question was really how long it would take, and what were the prospects for the next century or three.
The received wisdom seemed to be that we could expect about a metre, by 2100, and some studies limited SLR to about two metres in the next millennium. A new study suggests we could get close to two meters in total by 2100. Moreover the melting of ice on Antarctica alone could cause seas to rise more than 15 meters by 2500.Continue reading Ice sheet decay spells danger from sea level rise→
James Hansen worries that “we may be approaching a point of no return, a situation in which our children inherit a climate system undergoing changes that are out of their control, changes that will cause them irreparable harm”. He’s looked at the models, at current observations, and at what happened during the Eemian interglacial 118,000 years ago, and he doesn’t like what he sees.
During the Eemian, when global average temperatures were about 1°C more than now, sea level was about 3-4 metres higher than now for a considerable time. Then about 118,000 years ago, towards the end of the interglacial, it peaked at 6-9 meters, including a rise of 2-3 metres within several decades. A similar sea level rise of several metres now would see the inundation of many of the world’s major cities.
Back in 2011, we wrote about a fascinating new way to heat-treat regular, cheap steel to endow it with an almost miraculous blend of characteristics. Radically cheaper, quicker and less energy-intensive to produce, Flash Bainite is stronger than titanium by weight, and ductile enough to be pressed into shape while cold without thinning or cracking. It’s now being tested by three of the world’s five largest car manufacturers, Continue reading Climate clippings 160→
In a landmark public health finding, a new study from the Harvard School of Public Health finds that carbon dioxide (CO2) has a direct and negative impact on human cognition and decision-making. These impacts have been observed at CO2 levels that most Americans — and their children — are routinely exposed to today inside classrooms, offices, homes, planes, and cars.
…without drastic cuts in global greenhouse gas emissions–more drastic than any being discussed ahead of the critical climate meeting in Paris later this year—a rise of 20 metres will soon be unavoidable.