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Energy Videos and Webinars
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Training
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Videos and Webinars
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Engel Wachtler 1989.pdf
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TRB Library
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EDD-FIK
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Englund et al 1994.pdf
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TRB Library
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EDD-FIK
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Englund Heino 1994 two lakes.pdf
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TRB Library
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EDD-FIK
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Enhanced poleward moisture transport and amplified northern high-latitude wetting trend
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Observations and climate change projections forced by greenhouse gas emissions have indicated a wetting trend in northern high latitudes, evidenced by increasing Eurasian Arctic river discharges (1–3). The increase in river discharge has accelerated in the latest decade and an unprecedented, record high discharge occurred in 2007 along with an extreme loss of Arctic summer sea-ice cover (4–6). Studies have ascribed this increasing discharge to various factors attributable to local global warming effects, including intensifying precip- itation minus evaporation, thawing permafrost, increasing greenness and reduced plant transpiration7–11. However, no agreement has been reached and causal physical processes remain unclear. Here we show that enhancement of poleward atmospheric moisture transport (AMT) decisively contributes to increased Eurasian Arctic river discharges. Net AMT into the Eurasian Arctic river basins captures 98% of the gauged climatological river discharges. The trend of 2.6% net AMT increase per decade accounts well for the 1.8% per decade increase in gauged discharges and also suggests an increase in underlying soil moisture. A radical shift of the atmospheric circulation pattern induced an unusually large AMT and warm surface in 2006–2007 over Eurasia, resulting in the record high discharge.
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Climate Science Documents
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Enhanced Seasonal Exchange of CO2 by Northern Ecosystems Since 1960
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Seasonal variations of atmospheric carbon dioxide (CO2) in the Northern Hemisphere have increased since the 1950s, but sparse observations have prevented a clear assessment of the patterns of long-term change and the underlying mechanisms. We compare recent aircraft-based observations of CO2 above the North Pacific and Arctic Oceans to earlier data from 1958 to 1961 and find that the seasonal amplitude at altitudes of 3 to 6 km increased by 50% for 45° to 90°N but by less than 25% for 10° to 45°N. An increase of 30 to 60% in the seasonal exchange of CO2 by northern extratropical land ecosystems, focused on boreal forests, is implicated, substantially more than simulated by current land ecosystem models. The observations appear
to signal large ecological changes in northern forests and a major shift in the global carbon cycle.
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Climate Science Documents
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Environment, vegetation and greenness (NDVI) along the North America and Eurasia Arctic transects
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Satellite-based measurements of the normalized difference vegetation index (NDVI; an index of vegetation greenness and photosynthetic capacity) indicate that tundra environments are generally greening and becoming more productive as climates warm in the Arctic. The greening, however, varies and is even negative in some parts of the Arctic. To help interpret the space-based observations, the International Polar Year (IPY) Greening of the Arctic project conducted ground-based surveys along two >1500 km transects that span all five Arctic bioclimate subzones. Here we summarize the climate, soil, vegetation, biomass, and spectral information collected from the North America Arctic transect (NAAT), which has a more continental climate, and the Eurasia Arctic transect (EAT), which has a more oceanic climate. The transects have broadly similar summer temperature regimes and overall vegetation physiognomy, but strong differences in precipitation, especially winter precipitation, soil texture and pH, disturbance regimes, and plant species composition and structure. The results indicate that summer warmth and NDVI increased more strongly along the more continental transect.
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Climate Science Documents
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Ep. 89 Pheasants Forever And Precision Ag
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Ep. 89 Pheasants Forever and Precision Ag Pheasants Forever + Agriculture might not be the first combination you think of, but their similarities are far greater than one might expect. Tanner Bruce, Ag and Conservation Programs Manager at Pheasants Forever, joins podcast host Tony Kramer to talk conservation, precision farming, and the new partnership with Pheasants Forever and John Deere.
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Podcasts
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EPA 2006.pdf
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TRB Library
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EDD-FIK
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EPA and the Army Corps’ Proposed Rule to Define “Waters of the United States”
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Excerpt from summary : According to the agencies, the proposed rule would revise the existing regulatory definition of “waters of the United States” consistent with legal rulings—especially the Supreme Court cases—and science concerning the interconnectedness of tributaries, wetlands, and other waters to downstream waters and effects of these connections on the chemical, physical, and biological integrity of downstream waters. Waters that are “jurisdictional” are subject to the multiple regulatory requirements of the CWA: standards, discharge limitations, permits, and enforcement. Non-jurisdictional waters, in contrast, do not have the federal legal protection of those requirements.
This report describes the March 25 proposed rule and includes a table comparing the existing regulatory language that defines “waters of the United States” with that in the proposal.
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Climate Science Documents
