Walter C. Oechel

TL;DR: The FLUXNET project as mentioned in this paper is a global network of micrometeorological flux measurement sites that measure the exchanges of carbon dioxide, water vapor, and energy between the biosphere and atmosphere.

TL;DR: In this paper, the authors present asynthesis of these observations, and conclude that roughly half of the pronounced recent rise in Northern Hemispherewinter temperatures reflects shifts in atmosphericcirculation. But, such changes are not consistent with anthropogenic forcing and include generally positive phases of the North Atlantic and ArcticOscillations and extratropical responses to the El-NinoSouthern Oscillation.

TL;DR: A comprehensive evaluation of energy balance closure is performed across 22 sites and 50 site-years in FLUXNET, a network of eddy covariance sites measuring long-term carbon and energy fluxes in contrasting ecosystems and climates as mentioned in this paper.

TL;DR: In this article, the authors present a broad array of evidence that illustrates con- vincingly; the Arctic is undergoing a system-wide response to an altered climatic state.