Continental scale variation in 17 O-excess of meteoric waters in the United States

2015 ◽  
Vol 164 ◽  
pp. 110-126 ◽  
Author(s):  
Shuning Li ◽  
Naomi E. Levin ◽  
Lesley A. Chesson
2005 ◽  
Vol 24 (2) ◽  
pp. 269-296
Author(s):  
Charles H. David ◽  
Paul Dufour ◽  
Janet Halliwell

Canada, as a country with a small, open economy, faces the immediate challenge of learning to shape dynamic comparative advantage in the emerging international economy. About 75 % of Canada's trade linkages are with the United States, and a very large component of the Canadian experience of « globalization » is driven by North American economic integration. This integration is taking place in the absence of institutions and policy mechanisms to promote and manage science, technology, and innovation relations on a continental scale. Bilateral s & T arrangements centered on the United States presently characterize the North American innovation System. Circumstances in North America pose three sets of challenges to Canadian s & T policy. 1) Science and technology are increasing in importance in international trade, environmental, and social/cultural matters. This means that Canada must learn to improve its management of an increasingly internationalized domestic s & T System. 2) Canada must cultivate mutually beneficial bilateral s & T relationships with its two partners in NAFTA, Mexico and the United States. 3) Canada must identify where its interests lie in the development and governance of trilateral and international rules and arrangements for science, technology, and innovation.


2016 ◽  
Vol 50 (7) ◽  
pp. 3409-3415 ◽  
Author(s):  
John L. Stoddard ◽  
John Van Sickle ◽  
Alan T. Herlihy ◽  
Janice Brahney ◽  
Steven Paulsen ◽  
...  

2017 ◽  
Vol 122 (4) ◽  
pp. 875-885 ◽  
Author(s):  
Jean-Francois Lapierre ◽  
David A. Seekell ◽  
Christopher T. Filstrup ◽  
Sarah M. Collins ◽  
C. Emi Fergus ◽  
...  

PLoS ONE ◽  
2014 ◽  
Vol 9 (3) ◽  
pp. e91724 ◽  
Author(s):  
Michael G. Buhnerkempe ◽  
Michael J. Tildesley ◽  
Tom Lindström ◽  
Daniel A. Grear ◽  
Katie Portacci ◽  
...  

Science ◽  
2018 ◽  
Vol 361 (6407) ◽  
pp. 1115-1118 ◽  
Author(s):  
Benjamin M. Van Doren ◽  
Kyle G. Horton

Billions of animals cross the globe each year during seasonal migrations, but efforts to monitor them are hampered by the unpredictability of their movements. We developed a bird migration forecast system at a continental scale by leveraging 23 years of spring observations to identify associations between atmospheric conditions and bird migration intensity. Our models explained up to 81% of variation in migration intensity across the United States at altitudes of 0 to 3000 meters, and performance remained high in forecasting events 1 to 7 days in advance (62 to 76% of variation was explained). Avian migratory movements across the United States likely exceed 500 million individuals per night during peak passage. Bird migration forecasts will reduce collisions with buildings, airplanes, and wind turbines; inform a variety of monitoring efforts; and engage the public.


2010 ◽  
Vol 11 (6) ◽  
pp. 1380-1394 ◽  
Author(s):  
Matthew Sturm ◽  
Brian Taras ◽  
Glen E. Liston ◽  
Chris Derksen ◽  
Tobias Jonas ◽  
...  

Abstract In many practical applications snow depth is known, but snow water equivalent (SWE) is needed as well. Measuring SWE takes ∼20 times as long as measuring depth, which in part is why depth measurements outnumber SWE measurements worldwide. Here a method of estimating snow bulk density is presented and then used to convert snow depth to SWE. The method is grounded in the fact that depth varies over a range that is many times greater than that of bulk density. Consequently, estimates derived from measured depths and modeled densities generally fall close to measured values of SWE. Knowledge of snow climate classes is used to improve the accuracy of the estimation procedure. A statistical model based on a Bayesian analysis of a set of 25 688 depth–density–SWE data collected in the United States, Canada, and Switzerland takes snow depth, day of the year, and the climate class of snow at a selected location from which it produces a local bulk density estimate. When converted to SWE and tested against two continental-scale datasets, 90% of the computed SWE values fell within ±8 cm of the measured values, with most estimates falling much closer.


2021 ◽  
Vol 13 (18) ◽  
pp. 3631
Author(s):  
Austin Madson ◽  
Yongwei Sheng

Of the approximately 6700 lakes and reservoirs larger than 1 km2 in the Contiguous United States (CONUS), only ~430 (~6%) are actively gaged by the United States Geological Survey (USGS) or their partners and are available for download through the National Water Information System database. Remote sensing analysis provides a means to fill in these data gaps in order to glean a better understanding of the spatiotemporal water level changes across the CONUS. This study takes advantage of two-plus years of NASA’s ICESat-2 (IS-2) ATLAS photon data (ATL03 products) in order to derive water level changes for ~6200 overlapping lakes and reservoirs (>1 km2) in the CONUS. Interactive visualizations of large spatial datasets are becoming more commonplace as data volumes for new Earth observing sensors have markedly increased in recent years. We present such a visualization created from an automated cluster computing workflow that utilizes tens of billions of ATLAS photons which derives water level changes for all of the overlapping lakes and reservoirs in the CONUS. Furthermore, users of this interactive website can download segmented and clustered IS-2 ATL03 photons for each individual waterbody so that they may run their own analysis. We examine ~19,000 IS-2 derived water level changes that are spatially and temporally coincident with water level changes from USGS gages and find high agreement with our results as compared to the in situ gage data. The mean squared error (MSE) and the mean absolute error (MAE) between these two products are 1 cm and 6 cm, respectively.


2009 ◽  
Vol 24 (8) ◽  
pp. 1369-1381 ◽  
Author(s):  
Laurel G. Woodruff ◽  
William F. Cannon ◽  
Dennis D. Eberl ◽  
David B. Smith ◽  
James E. Kilburn ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document