The wreckage stalling acceptance on global warming comes from a collision between questionable predictions and compelling time frames. Here’s how to clear the wreckage and make progress.
Global warming predicts our planet’s average temperature should continue to rise and cause both beneficial and damaging results for all life.
Questionable predictions are a major issue in many fields, according to Nate Silver in his 2012 book, The Signal and the Noise. He’s the statistician, blogger and NYT columnist who predicted the correct results for every state and the US in the 2012 presidential election.
“We love to predict things—and we aren’t very good at it,” he said. “We must become more comfortable with probability and uncertainty. We must think more carefully about the assumptions […] we bring to a problem.”
Silver said meteorologists make increasingly accurate forecasts of temperature because they describe present conditions and state assumptions about incoming clouds and pressure systems. Data is fed into computer models for predictions with stated probabilities. Prediction data provides feedback to verify assumptions and improve models.
Predictions on global temperatures must use the same processes but have less data and more difficult assumptions. Fortunately they start with a highly accurate mathematical model called the Greenhouse Effect.
Water vapor, carbon dioxide, methane and ozone in the atmosphere trap heat from the sun causing a planetary greenhouse effect according to a consensus of hundreds of scientists at the first UN International Panel on Climate Change (IPCC).
“There is a natural greenhouse effect that keeps the earth warmer than it otherwise would be,” said the IPCC in 1990.
IPCC scientists accurately measure natural gas emissions and the increasing gas emissions from smoke stacks and exhaust pipes. They unanimously agreed they’ll warm the planet.
“Emissions resulting from human activities are substantially increasing the atmospheric concentrations of the greenhouse gases,” said the IPCC scientists. “These increases will enhance the greenhouse effect, resulting in additional warming of the Earth’s surface.”
Hooray! Silver ‘s research confirmed scientists believe they have adequate data for temperature and gas concentrations In present conditions. Historical analysis requires mathematical adjustments to temperature data for special effects caused by solar cycles, El Nino and volcanoes.
But assumptions for future scenarios are troublesome. And there’s no agreement on the length of time for accurate predictions, so scientists and doubters are creating reckless confusion by choosing random dates to make monthly, annual, five- and up to 100-year forecasts. Meteorologists don’t trust such contradictory forecasts.
Silver met Gavin Schmidt, a highly respected statistician, climatologist and blogger who recommends a 25-year time frame to minimize randomness and maximize reliability.
Silver used six independent computer models from different agencies using different data sources.
“All six show a clear long-term warming trend,” he said.
So what? Since our planet’s average temperature from mountain top to Arabian desert is 32 degrees F, even relatively minor warming trends help explain why ice melts are accelerating on mountain tops and polar caps.
OK, if scientists agreed on 25-year forecasts, could policy makers agree on action?
Probably not. Policy makers are hearing questionable predictions. Predictions on sea levels in 2050 use such elaborate mathematical models unimproved by feedback that Silver found only 19 percent of climatologists have confidence in them.
Those forecasts convinced Holland and some coastal communities to protect themselves from higher seas surging over their dykes and waterfronts. But how can policy makers in less threatened areas build support from uncertain generalized risks?
And contrast the time needed to build scientific consensus compared to build political consensus in a world of daily broadcasts, quarterly business reports and two-year congressional election cycles. The media asked scientists if Hurricane Sandy was proof of global warming. Business understandably resists changes without better predictions. Energy firms spend hundreds of millions to increase confusion rather than clarify it.
The best evidence predicts our planet is getting warmer, bringing beneficial and damaging, possibly catastrophic changes to our life. We should demand scientific rigor to improve predictions and insist the media and skeptics clarify issues.
We need cooperation to maintain this greenhouse planet that keeps us alive.