Ators of alter are NDVI and the active layer thickness. Keyword phrases Alaska Toolik Velneperit Climate adjust Ecological effects Greenland Zackenberg Medium pass filter VegetationINTRODUCTION Climate warming in the Arctic, substantial more than current decades and well-documented in IPCC reports (IPCC 2001, 2013), is reflected in alterations in a wide variety of environmental and ecological measures. These illustrate convincingly that the Arctic is undergoing a system-wide response (ACIA 2005; Hinzman et al. 2005). The altering measures variety from physical state variables, for example air temperature, permafrost temperature (Romanovsky et al. 2010), or the depth of seasonal thaw (Goulden et al. 1998),to changes in ecological processes, like plant growth, which can result in modifications inside the state of ecosystem components for instance plant biomass or changes in ecosystem structure (Chapin et al. 2000; Sturm et al. 2001; Epstein et al. 2004). In spite with the substantial quantity of environmental and ecological measurements created more than recent decades, it has proven difficult to uncover statistically substantial trends in these measurements. This difficulty is brought on by the higher annual and seasonal variability of warming inside the air temperature and also the complexity of biological interactions. 1 remedy for the variability dilemma is to carry 
out long-term studies. These studies are costly to carry out within the Arctic with all the outcome that many detailed studies have been relatively short-term (e.g., the IBP Arctic projects in the U.S. and Canada), or have already been long-term projects restricted in scope (e.g., the Sub-Arctic Stordalen project in Abisko, Sweden; Jonasson et al. 2012). At the moment, you’ll find but two projects underway that happen to be each long-term and broad in scope: Toolik inside the Low Arctic of northern Alaska and Zackenberg in the High Arctic of northeast Greenland (Fig. 1). Right here we use data from these web pages to ask which varieties of measures really yield statistically significant trends of effects of climate warming Additional, are there frequent characteristics of those useful measures that minimize variabilitySTUDY Sites The Toolik project (Table 1) is located in the University of Alaska’s Toolik Field Station (TFS) some 125 km inland in the Arctic Ocean. The Long term Ecological Analysis (LTER)1 and connected projects at this site havehttp:arc-lter.ecosystems.mbl.edu.The Author(s) 2017. This short article is published with open access at Springerlink.com www.kva.seenAmbio 2017, 46(Suppl. 1):S160SFig. 1 Location of Toolik, Alaska (68o380 N, 149o430 W) and Zackenberg, Greenland (74o300 N, 21o300 W), long-term arctic study sitesTable 1 Ecological settings for Toolik and Zackenberg investigation web pages Toolik field station Location Inland, Northern Alaska 68o380 N, 149o430 W, 719 m altitude Physical Rolling foothills, Continuous permafrost (200 m), annual setting temperature -8 , summer (mid-June to mid-August) 9 , annual precipitation 312 mm Ecology Tussock tundra (sedges, evergreen PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/21301389 and deciduous shrubs, forbs, mosses, and lichens). Low shrubs, birches, and willows grow involving tussocks and along water tracks and stream banks. Low Arctic LTER (Long term Ecological Research), ITEX (International Tundra Experiment), NOAA’s Arctic System, CALM (Circumpolar Active Layer Monitoring), and the TFS environmental monitoring plan Zackenberg Coast, Northeast Greenland 74o300 N, 21o300 W, 0 m altitude Mountain valley, Continuous permafrost (estimated 20000 m), annual temperature -8 , summer season (three months) four.five , an.