Live Earth, founded by producer Kevin Wall, in partnership with former Vice President Al Gore, is a for-profit company that uses concerts, media and other events to encourage awareness worldwide about environmental issues.
"They've had no influence or involvement of any kind with the report itself," he said. "That is entirely under the control of the 26 authors from the eight countries, all widely respected -- and many of them are lead authors of IPCC studies. They're known quantities in the peer-reviewed science world."
Though this report is not "officially" from the IPCC, which makes no provisions for comprehensive mid-term reports halfway through its five- or six-year reporting cycle, Somerville said he and his fellow authors expect that it will be accepted by their peers in climate research around the world.
"This report is firmly based on more than 200 recent peer-reviewed papers clearly listed in the report," he said.
The authors said they were aiming not only at policy makers, but also at the general public.
Common misconceptions about global warming are dealt with in separate side-bar boxes, explaining why, for example, the human-induced warming has not slowed or paused, contrary to some recent headlines.
The authors also give a relatively reassuring assessment about the chances of an uncontrollable "runaway" global temperature rise in the near future.
Their findings include:
Sea Level Rise this century is likely to be "at least twice that projected" three years ago, with enormous humanitarian and economic impacts.
It could well be around three feet before the year 2100, says the report. Just a fraction of that increase in sea level could displace many millions of people and greatly increase vulnerability to storms.
A sea-level rise of 6 ½ feet is now considered by the scientists to be a reasonable "upper bound" of estimates -- a distinct possibility.
All ice types, including massive ice sheets, mountain glaciers and Arctic sea ice (frozen sea-surface), are for the most part melting far faster than predicted three years ago.
Greenhouse gas emissions that cause global warming are surging, with global emissions from burning fossil fuels now 40 percent higher than in 1990 and climbing.
Scientists are at constant pains to point out that recent (or any) slight and brief emissions drops in a few countries cause no reduction of the greenhouse gas concentrations in the atmosphere that set the global temperature thermostat.
This is because CO2 emissions stay in the air, on average, for hundreds of years.
Somerville and other scientists say they frequently have to make sure people they talk to understand the difference between "emissions" -- the amount of additional heat-trapping gas humanity puts in the atmosphere per year, and "concentrations" -- the amount of those gases that has piled up in the atmosphere and goes on hanging there for a long time.
Concentrations, which are measured in parts per million, have been rising steadily since the beginning of the industrial age some two centuries ago.