Debate and Business Challenges

 A lot of the warming took place between 1970 and 1998  If warming continues at the average rate from 1910 to 2000, effects on civilization will be severe  There are strong reasons to believe that at least some of the warming after 1970 has been created by business activity

The recent climate record according to 3 “standard” models

 Beyond these basic points, everything is controversial  95%+ of professional climate scientists don’t agree with my statement that things are controversial, but …

 Most climate scientists believe what we are doing to the planet (increasing emissions of carbon dioxide, methane) is certain to cause catastrophe  But a few do not ◦ Richard Lenzen, Alfred Sloan Professor of Climate Science at M.I.T. ◦ John Christy, NOAA-funded researcher at U. of Alabama  Experts in seemingly related fields are skeptical ◦ Forecasting, decision science  The stakes are high

 contradictory claims;  threat that we may seriously damage civilization.  A big question: Just what is our responsibility?

 Much of human history took place during ice ages  Emergence of agriculture and spurt in population took place just after a moderate warming ◦ After that climate was unusually stable  Warming was noted in the 1930s, continued to the 40s, but was reversed ◦ Maybe because this was the era of high particulate- emitting cars and factories in America and Europe?

 Warming resumed after 1971  Today the earth is at least 1 〫 or so warmer than in 1910

 Most are poorly understood  But clearly, some gases let more heat come in than they allow to go out ◦ Business activity is increasing the amount of these gases

 And some things humans do make things cooler ◦ Soot in the atmosphere  Mainstream climate scientists’ models suggest current trends lead to 3 〫 more warming by 2010 ◦ and much more heating after that ◦ Carbon burned today stays in atmosphere a long time  Many climate scientists thing things will be worse ◦ They’re asked to be ‘cautious’ in their projections ◦ Today’s models don’t include recent developing world acceleration

 Heat waves  Stronger hurricanes  Change in locations where rain falls  Higher sea levels  Less food production in tropical countries ◦ But more food production further from the equator  Not necessarily the end of civilization, but not a world we’d like to see

 John Christy, a co-author of the original IPCC reports, says: ◦ Standard estimates overstate warming because of urbanization around the temperature measuring sites  Parking lots, new air conditioners, buildings radiating heat have been created near some measuring equipment ◦ Christy & Spenser measure temperature using NASA satellite data, get much lower numbers ◦ “The real atmosphere has many ways to respond to the changes that increased CO2 forces on it”  Some data suggests as earth warms, cloud cover increases, limiting warming

 In recent decades, researchers in forecasting and decision sciences have tried to identify when ‘expert opinion’ is reliable  Their rules say: Create a simple causal model  They say if the model is complex and contains lots of uncertainty, it isn’t reliable ◦ So they’re skeptical about standard climate scientists  Armstrong (forecasting expert) says: do nothing  Christy says: Build nuclear power

 Yes, often. Some non-successes ◦ Psychological testing programs ◦ Econometric forecasting ◦ Psychoanalysis  But probably never with such high stakes

 At minimum, the global warming story is a careful but potentially fallible weather forecast ◦ It may be wrong ◦ But so might the forecasts today on weather.com ◦ The fact that forecasts might be wrong doesn’t prevent us from refusing to go on picnics when forecasts say it will rain

 Standard science argues it’s important to keep global temperatures from rising more than 2 〫  Standard estimates suggest big declines in greenhouse gas emissions are needed to keep rise to that level ◦ Because carbon entering atmosphere today stays for 200 years or so, gas produced post-WW II is just beginning to affect the earth ◦ Demanded cut are unlike anything close to passing Congress  A WW II-level mobilization?

 Energy is by many measures the world’s largest industry  If it’s changing rapidly, there will be lots of opportunity ◦ (If China’s currency is undervalued, the opportunity may go to China)

 Government will remake the energy world ◦ Silicon Valley business can prosper ◦ It won’t be surprising if others resent us  While many businesspeople may prosper, there will be need for many to sacrifice