The State of Climate Change Science

Richard Lindzen, professor emeritus of atmospheric sciences at MIT, writes at WSJ:

Research in recent years has encouraged those of us who question the popular alarm over allegedly man-made global warming. Actually, the move from “global warming” to “climate change” indicated the silliness of this issue. The climate has been changing since the Earth was formed. This normal course is now taken to be evidence of doom.

Individuals and organizations highly vested in disaster scenarios have relentlessly attacked scientists and others who do not share their beliefs. The attacks have taken a threatening turn.

As to the science itself, it’s worth noting that all predictions of warming since the onset of the last warming episode of 1978-98—which is the only period that the United Nations Intergovernmental Panel on Climate Change (IPCC) attempts to attribute to carbon-dioxide emissions—have greatly exceeded what has been observed. These observations support a much reduced and essentially harmless climate response to increased atmospheric carbon dioxide.

In addition, there is experimental support for the increased importance of variations in solar radiation on climate and a renewed awareness of the importance of natural unforced climate variability that is largely absent in current climate models. There also is observational evidence from several independent studies that the so-called “water vapor feedback,” essential to amplifying the relatively weak impact of carbon dioxide alone on Earth temperatures, is canceled by cloud processes.

There are also claims that extreme weather—hurricanes, tornadoes, droughts, floods, you name it—may be due to global warming. The data show no increase in the number or intensity of such events. The IPCC itself acknowledges the lack of any evident relation between extreme weather and climate, though allowing that with sufficient effort some relation might be uncovered.

World leaders proclaim that climate change is our greatest problem, demonizing carbon dioxide. Yet atmospheric levels of carbon dioxide have been vastly higher through most of Earth’s history. Climates both warmer and colder than the present have coexisted with these higher levels.

Currently elevated levels of carbon dioxide have contributed to increases in agricultural productivity. Indeed, climatologists before the recent global warming hysteria referred to warm periods as “climate optima.” Yet world leaders are embarking on costly policies that have no capacity to replace fossil fuels but enrich crony capitalists at public expense, increasing costs for all, and restricting access to energy to the world’s poorest populations that still lack access to electricity’s immense benefits.