In my previous post Climate sensitivity: lopping off the fat tail, I argued that it is becoming increasingly difficult to defend high values of ECS. However, the uncertainty is sufficiently large that we can’t really identify a meaningful ‘best value’ of sensitivity, or rule out really high values.
A key issue is that emerging estimates of aerosol forcing are considerably lower than what was used in the AR5 determinations of ECS, implying lower values of ECS than was determined by the AR5.
This uncertainty in ECS makes emission targets rather meaningless. It will be interesting to see how this uncertainty is factored into the Paris negotiations
Note, there are other papers on this general topic that are in the review process, I expect a spate of such papers to appear during the next month.
You can imagine the horror on the signatories’ faces when they realised that some very determined people were about to take a close interest in their financial arrangements and those of their colleagues at IGES.
I’m not sure taking the letter down is going to help much though.
If settlement is the goal, Apollo redux is dead. Giant expendable government rockets hurling government employees and return vehicles at Mars won’t cut it in the long run. The main reason to do so is government public relations, as the heroes return and share their stories. If settlement is the goal, we send other kinds of PR heroes — settlers — who land and live out their days on camera, building the first community as more and more follow. Again, it’s different models. One model works for government, the other for private ventures. And since the one-way model is so much cheaper, and the people who will have working one-way systems first are private sector, they may well beat the government to Mars.
He proposes a much more viable approach, but for now, it’s politically unrealistic. Congress doesn’t want to send people to Mars. It wants to build big rockets.
"If settlement is the goal, Apollo redux is dead."
And if settlement is not the goal govt HSF is a waste of money.
http://t.co/GM5ksrGSvC
It’s stiff competition, but this may, in fact, be the stupidest space piece ever written. As Stephen Green says, the Left jumps the shark, in a rocketship.
The Senate Launch System is four years old (if you count from when NASA actually rolled out the design — it’s more like five years when it was first stipulated in the NASA authorization bill). Some thoughts at the time from Jerry Pournelle.
And Stephen Smith has a history of Orion (the capsule, not the nuclear-powered spacecraft, which just slipped another two years, and even NASA is no longer pretending will ever go to Mars):
SpaceX spent 100% of its own money to develop the Falcon 9 booster and the upcoming Falcon Heavy. The cargo Dragon capsule cost $850 million to develop; $400 million was NASA seed money, while $450 million was SpaceX money. It was only four years from SpaceX receiving its first commercial cargo contract in August 2006 to the first test flight in December 2010. The first Dragon delivery was in May 2012. Dragon was designed with the eventual goal of using it for people, so the crewed Dragon V2 would seem likely to avoid much of the design delays that might plague other commercial crew companies.
Orion and SLS have no urgency, because there’s no profit motive. The contractors get paid regardless of their pace or success; it’s required by law. Their lobbyists ensure through generous campaign contributions that Congress will prohibit any competition. Representatives of NASA space centers populate the space authorization and appropriations committees in the House and the Senate; their priority, sometimes stated explicitly, is to protect the taxpayer-funded government jobs in their districts and states.
Maybe, someday, we’ll actually see NASA crew climb into an Orion capsule atop a Space Launch System booster at Pad 39B. But it will be tens of billions of dollars after we see commercial crew companies do it for far cheaper.
Yup. I’d bet it never happens. It certainly shouldn’t.