Serious Flaws Uncovered in ‘4,000 Year’ Warming Paper

Serious Flaws Uncovered in ‘4,000 Year’ Warming Paper
March 15, 2013

James M. Taylor

James M. Taylor is senior fellow for environment and energy policy at The Heartland Institute.... (read full bio)

Climate Change Weekly #84

The mainstream media is reporting in breathless fashion about a new paper claiming current temperatures are their warmest in 4,000 years. Already, however, scientists are reporting serious flaws in the paper. The media may wish to paint a picture of runaway global warming, but the science tells a completely different story.

Recently graduated Ph.D. student Shaun Marcott has published a paper claiming he compiled a proxy temperature reconstruction indicating current temperatures are their warmest in at least 4,000 years. Proxy temperature reconstructions require careful scrutiny because the proxies are not direct temperature measurements, but represent other data and factors that may or may not have a close correlation with past temperatures. Some proxies are better than others. Also, an agenda-driven researcher can easily cherry-pick certain anomalous proxies that support a predetermined conclusion while ignoring a much larger set of proxies that tell a different story.

Although scientists have had little time so far to dig into the meat of Marcott’s data, methods, and conclusions, their initial observations are devastating. Don Easterbrook, geology professor emeritus at Western Washington University, has published two papers summarizing and documenting many of the already-discovered flaws in Marcott’s reconstruction. Easterbrook reports at least one more paper is on the way exposing flaws and areas of concern in Marcott’s reconstruction.

Easterbrook points out 80 percent of the data used by Marcott reflect oceanic data, not atmospheric temperatures. “Thus, they may reflect temperature changes from ocean upwelling, changes in ocean currents, or any one of a number of ocean variations not related to atmospheric climates,” Easterbrook writes. Marcott’s heavy dependence on oceanic rather than atmospheric proxies “in itself means that the Marcott et al. temperatures are not a reliable measure of changing atmospheric climate,” Easterbrook reports.

Easterbrook also notes Marcott recycled Michael Mann’s proxies to help compile the small portion of Marcott’s land-based proxies. Discredited proxies by any other name are still discredited proxies.

Perhaps most damaging, Easterbrook observes many other published studies and data, including analysis of extremely reliable Greenland ice core data, contradict Marcott’s asserted proxy data.

When many temperature studies, including studies presented by the United Nations Intergovernmental Panel on Climate Change, indicate current global temperatures are cooler than the vast majority of the past 4,000 years, and then an outlier study with quickly identified serious flaws claims the opposite, one would think the media would make note of the discrepancies. Unfortunately, the media has demonstrated little interest in doing so.

SOURCES: Watts Up With That? and Watts Up With That?


New batch of Climategate emails on the way … Obama to federal agencies: weigh climate concerns … Krugman suggests skeptics will go to hell … Antarctic sea ice sets more records this week … Polar sea ice remains above the long-term average


An anonymous whistleblower released a third batch of Climategate emails this week. The whistleblower did not release the emails to the general public, but instead asked trustworthy global warming experts to review the emails and sift scientifically noteworthy emails from those that are personal or off-topic. The Climategate 3.0 emails are likely to be released during the upcoming weeks and months.

SOURCE: Watts Up With That?


President Barack Obama is preparing to tell U.S. federal agencies they must take global warming into consideration before approving any major projects. The directive will place a wide range of projects in jeopardy, including road construction, energy production, and coal and natural gas export facilities.

SOURCE: Bloomberg


New York Times columnist Paul Krugman spewed more venom at global warming skeptics, suggesting they will be sent to hell for their “denial.” In his March 15 column Krugman writes, “You can deny global warming (and may you be punished in the afterlife for doing so -- this kind of denial for petty personal or political reasons is an almost inconceivable sin).”

SOURCE: New York Times


Antarctic sea ice set additional records this week. So far during 2013, Antarctic sea ice extent has set records on eight separate dates. By comparison, there are only seven dates in the entire calendar year when the greatest extent of Antarctic sea ice occurred before 2000.

SOURCES: Sunshine Hours; Sunshine Hours; and Cryosphere Today


The total amount of global sea ice is significantly above the long-term average, as Arctic sea ice is close to the long-term mean and Antarctic sea ice is at record extent. The Antarctic and global sea ice extent strongly contradict assertions by global warming alarmists that below-average Arctic sea ice reflects receding polar ice caps and an imminent global warming crisis.

SOURCE: Cryosphere Today

James M. Taylor

James M. Taylor is senior fellow for environment and energy policy at The Heartland Institute.... (read full bio)