Berkeley Earth founder Richard A. Muller told The Guardian ...we are bringing the spirit of science back to a subject that has become too argumentative and too contentious, ....we are an independent, non-political, non-partisan group.

[3] Large donors include Lawrence Berkeley National Laboratory, the Charles G. Koch Foundation, the Fund for Innovative Climate and Energy Research (FICER),[4] and the William K. Bowes Jr.

The study addressed scientific concerns including the urban heat island effect, poor station quality, and the risk of data selection bias.

The Berkeley Earth group concluded that the warming trend is real, that over the past 50 years (between the decades of the 1950s and 2000s) the land surface warmed by 0.91±0.05 °C, and their results mirror those obtained from earlier studies carried out by the U.S. National Oceanic and Atmospheric Administration (NOAA), the Hadley Centre, NASA's Goddard Institute for Space Studies (GISS) Surface Temperature Analysis, and the Climatic Research Unit (CRU) at the University of East Anglia.

[7][8][9] The Berkeley Earth study addressed scientific concerns raised by skeptics including urban heat island effect, poor station quality, and the risk of data selection bias.

The methodology also avoids traditional procedures that require long, continuous data segments, thus accommodating short sequences, such as those provided by temporary weather stations.

This innovation allowed the group to compile an earlier record than its predecessors, starting from 1800, but with a high degree of uncertainty because at the time there were only two weather stations in America, just a few in Europe and one in Asia.

[8][16] Given project leader Muller's well-publicized concerns regarding the quality of climate change research, other critics anticipated that the Berkeley Earth study would be a vindication of their stance.

"[18] Stephen McIntyre, editor of Climate Audit, a climate-skeptics blog, said that "the team deserves credit for going back to the primary data and doing the work" and even though he had not had an opportunity to read the papers in detail, he questioned the analyses of urban heating and weather station quality.

James Hansen, a leading climate scientist and head of NASA Goddard Institute for Space Studies commented that he had not yet read the research papers but was glad Muller was looking at the issue.

"[10] Phil Jones the director of the Climatic Research Unit (CRU) at the University of East Anglia, said: "I look forward to reading the finalised paper once it has been reviewed and published.

"[20] Peter Thorne, from the Cooperative Institute for Climate and Satellites in North Carolina and chair of the International Surface Temperature Initiative, said: "This takes a very distinct approach to the problem and comes up with the same answer, and that builds confidence that pre-existing estimates are in the right ballpark.