This assessment would not have been possible without the cooperation and contributions from various scientists representing a cross section of the NOAA climate community. We also wish to acknowledge the contributions from the scientists outside of NOAA in other federal laboratories, at universities, and at several sites around the world. All of these scientists are in the contributors list (appendix) and we thank them for their timely and useful input. We are especially grateful to those international scientists who contributed their time and effort. In addition, we would like to thank J. Janowiak, and the anonymous reviewers for their comments that helped to strengthen the article. This assessment is supported by a grant from the NOAA Office of Global Program’s Climate Change Data and Detection Program.