Changes in Snowmelt Runoff Timing in the Contiguous United States

2021 ◽  
Author(s):  
Sukru Uzun ◽  
Tugkan Tanir ◽  
Gustavo de A. Coelho ◽  
Andre de Souza Lima ◽  
Felicio Cassalho ◽  
...  
2020 ◽  
Vol 6 (49) ◽  
pp. eaba5939
Author(s):  
Evan N. Dethier ◽  
Shannon L. Sartain ◽  
Carl E. Renshaw ◽  
Francis J. Magilligan

Complex hydroclimate in the United States and Canada has limited identification of possible ongoing changes in streamflow. We address this challenge by classifying 541 stations in the United States and Canada into 15 “hydro-regions,” each with similar seasonal streamflow characteristics. Analysis of seasonal streamflow records at these stations from 1910 to present indicates regionally coherent changes in the frequency of extreme high- and low-flow events. Where changes are significant, these events have, on average, doubled in frequency relative to 1950 to 1969. In hydro-regions influenced by snowmelt runoff, extreme high-flow event frequency has increased despite snowpack depletion by warming winter temperatures. In drought-prone hydro-regions of the western United States and Southeast, extreme low-flow event frequency has increased, particularly during summer and fall. The magnitude and regional consistency of these hydrologic changes warrant attention by watershed stakeholders. The hydro-region framework facilitates quantification and further analyses of these changes to extreme streamflow.


2005 ◽  
Vol 6 (4) ◽  
pp. 476-482 ◽  
Author(s):  
Gregory J. McCabe ◽  
Martyn P. Clark

Abstract The timing of snowmelt runoff (SMR) for 84 rivers in the western United States is examined to understand the character of SMR variability and the climate processes that may be driving changes in SMR timing. Results indicate that the timing of SMR for many rivers in the western United States has shifted to earlier in the snowmelt season. This shift occurred as a step change during the mid-1980s in conjunction with a step increase in spring and early-summer atmospheric pressures and temperatures over the western United States. The cause of the step change has not yet been determined.


Author(s):  
John M. Wehrung ◽  
Richard J. Harniman

Water tables in aquifer regions of the southwest United States are dropping off at a rate which is greater than can be replaced by natural means. It is estimated that by 1985 wells will run dry in this region unless adequate artificial recharging can be accomplished. Recharging with surface water is limited by the plugging of permeable rock formations underground by clay particles and organic debris.A controlled study was initiated in which sand grains were used as the rock formation and water with known clay concentrations as the recharge media. The plugging mechanism was investigated by direct observation in the SEM of frozen hydrated sand samples from selected depths.


Author(s):  
A. Hakam ◽  
J.T. Gau ◽  
M.L. Grove ◽  
B.A. Evans ◽  
M. Shuman ◽  
...  

Prostate adenocarcinoma is the most common malignant tumor of men in the United States and is the third leading cause of death in men. Despite attempts at early detection, there will be 244,000 new cases and 44,000 deaths from the disease in the United States in 1995. Therapeutic progress against this disease is hindered by an incomplete understanding of prostate epithelial cell biology, the availability of human tissues for in vitro experimentation, slow dissemination of information between prostate cancer research teams and the increasing pressure to “ stretch” research dollars at the same time staff reductions are occurring.To meet these challenges, we have used the correlative microscopy (CM) and client/server (C/S) computing to increase productivity while decreasing costs. Critical elements of our program are as follows:1) Establishing the Western Pennsylvania Genitourinary (GU) Tissue Bank which includes >100 prostates from patients with prostate adenocarcinoma as well as >20 normal prostates from transplant organ donors.


Author(s):  
C. D. Humphrey ◽  
C.S. Goldsmith ◽  
L. Elliott ◽  
S.R. Zaki

An outbreak of unexplained acute pulmonary syndrome with high fatality was recognized in the spring of 1993 in the southwestern United States. The cause of the illness was quickly identified serologically and genetically as a hantavirus and the disease was named hantavirus pulmonary syndrome (HPS). Recently, the virus was isolated from deer mice which had been trapped near the homes of HPS patients, and cultivated in Vero E6 cells. We identified the cultivated virus by negative-stain direct and colloidal gold immune electron microscopy (EM).Virus was extracted, clarified, and concentrated from unfixed and 0.25% glutaraldehyde fixed supernatant fluids of infected Vero E6 cells by a procedure described previously. Concentrated virus suspensions tested by direct EM were applied to glow-discharge treated formvar-carbon filmed grids, blotted, and stained with 0.5% uranyl acetate (UA) or with 2% phosphotungstic acid (PTA) pH 6.5. Virus suspensions for immune colloidal gold identification were adsorbed similarly to filmed grids but incubated for 1 hr on drops of 1:50 diluted monoclonal antibody to Prospect Hill virus nucleoprotein or with 1:50 diluted sera from HPS virus infected deer mice.


Author(s):  
Vinod K. Berry ◽  
Xiao Zhang

In recent years it became apparent that we needed to improve productivity and efficiency in the Microscopy Laboratories in GE Plastics. It was realized that digital image acquisition, archiving, processing, analysis, and transmission over a network would be the best way to achieve this goal. Also, the capabilities of quantitative image analysis, image transmission etc. available with this approach would help us to increase our efficiency. Although the advantages of digital image acquisition, processing, archiving, etc. have been described and are being practiced in many SEM, laboratories, they have not been generally applied in microscopy laboratories (TEM, Optical, SEM and others) and impact on increased productivity has not been yet exploited as well.In order to attain our objective we have acquired a SEMICAPS imaging workstation for each of the GE Plastic sites in the United States. We have integrated the workstation with the microscopes and their peripherals as shown in Figure 1.


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