The conservation value of high elevation habitats to North American migrant birds

2015 ◽  
Vol 192 ◽  
pp. 461-476 ◽  
Author(s):  
W. Alice Boyle ◽  
Kathy Martin
Keyword(s):  
North American ◽  
High Elevation ◽  
Conservation Value ◽  
Migrant Birds

scholarly journals Snow-to-Liquid Ratio Variability and Prediction at a High-Elevation Site in Utah’s Wasatch Mountains

2010 ◽  
Vol 25 (1) ◽  
pp. 323-337 ◽  
Author(s):  
Trevor I. Alcott ◽  
W. James Steenburgh
Keyword(s):  
North American ◽  
Snow Water Equivalent ◽  
Winter Season ◽  
Predictive Ability ◽  
High Elevation ◽  
Reanalysis Data ◽  
Precipitation Forecast ◽  
Atmospheric Conditions ◽  
Liquid Ratio ◽  
High Elevation Site

Abstract Contemporary snowfall forecasting is a three-step process involving a quantitative precipitation forecast (QPF), determination of precipitation type, and application of a snow-to-liquid ratio (SLR). The final step is often performed using climatology or algorithms based primarily on temperature. Based on a record of consistent and professional daily snowfall measurements, this study 1) presents general characteristics of SLR at Alta, Utah, a high-elevation site in interior North America with frequent winter storms; 2) diagnoses relationships between SLR and atmospheric conditions using reanalysis data; and 3) develops a statistical method for predicting SLR at the study location. The mean SLR at Alta is similar to that observed at lower elevations in the surrounding region, with substantial variability throughout the winter season. Using data from the North American Regional Reanalysis, temperature, wind speed, and midlevel relative humidity are shown to be related to SLR, with the strongest correlation occurring between SLR and near-crest-level (650 hPa) temperature. A stepwise multiple linear regression (SMLR) equation is constructed that explains 68% of the SLR variance for all events, and 88% for a high snow-water equivalent (>25 mm) subset. To test predictive ability, the straightforward SMLR approach is applied to archived 12–36-h forecasts from the National Centers for Environmental Prediction Eta/North American Mesoscale (Eta/NAM) model, yielding an improvement over existing operational SLR prediction techniques. Errors in QPF over complex terrain, however, ultimately limit skill in forecasting snowfall amount.

scholarly journals Large Contribution of Coarse Mode to Aerosol Microphysical and Optical Properties: Evidence from Ground-Based Observations of a Transpacific Dust Outbreak at a High-Elevation North American Site

2017 ◽  
Vol 74 (5) ◽  
pp. 1431-1443 ◽  
Author(s):  
E. Kassianov ◽  
M. Pekour ◽  
C. Flynn ◽  
L. K. Berg ◽  
J. Beranek ◽  
...  
Keyword(s):  
North American ◽  
High Elevation ◽  
Saharan Dust ◽  
Large Contribution ◽  
Near Surface ◽  
Dust Transport ◽  
Aerosol Mass ◽  
Coarse Mode ◽  
Median Diameter ◽  
Transpacific Transport

Abstract This work is motivated by previous studies of transatlantic transport of Saharan dust and the observed quasi-static nature of coarse mode aerosol with a volume median diameter (VMD) of approximately 3.5 μm. The authors examine coarse mode contributions from transpacific transport of dust to North American aerosol properties using a dataset collected at the high-elevation Storm Peak Laboratory (SPL) and the nearby Atmospheric Radiation Measurement (ARM) Mobile Facility. Collected ground-based data are complemented by quasi-global model simulations and satellite and ground-based observations. The authors identify a major dust event associated mostly with a transpacific plume (about 65% of near-surface aerosol mass) in which the coarse mode with moderate (~3 μm) VMD is distinct and contributes substantially to total aerosol volume (up to 70%) and scattering (up to 40%). The results demonstrate that the identified plume at the SPL site has a considerable fraction of supermicron particles (VMD ~3 μm) and, thus, suggest that these particles have a fairly invariant behavior despite transpacific transport. If confirmed in additional studies, this invariant behavior may simplify considerably parameterizations for size-dependent processes associated with dust transport and removal.

scholarly journals Interannual variability of ozone and carbon monoxide at the Whistler high elevation site: 2002–2006

2011 ◽  
Vol 11 (22) ◽  
pp. 11431-11446 ◽  
Author(s):  
A. M. Macdonald ◽  
K. G. Anlauf ◽  
W. R. Leaitch ◽  
E. Chan ◽  
D. W. Tarasick
Keyword(s):  
North American ◽  
Forest Fires ◽  
High Elevation ◽  
Yukon Territory ◽  
Back Trajectory ◽  
Late Winter ◽  
Monthly Means ◽  
Air Masses ◽  
Mixing Ratios ◽  
Western Us

Abstract. In spring 2002, an atmospheric measurement site was established at the peak of Whistler Mountain in British Columbia, Canada to measure trace gases, particle chemistry and physics, and meteorology. This paper uses continuous measurements from March 2002 to December 2006 to investigate the influence of trans-Pacific transport and North American forest fires on both O3 and CO at Whistler. Annual mean mixing ratios of O3 and CO were 41 ppbv (monthly means of 35–48 ppbv) and 145 ppbv (monthly means of 113–177 ppbv) respectively with both species exhibiting an annual cycle of late-winter to early-spring maxima and summer minima. The absence of a broad summer O3 peak differs from previously-reported high altitude sites in the western US. The highest monthly-averaged O3 and CO mixing ratios relative to the 5-yr monthly means were seen in fall 2002 and spring 2003 with increased O3 and CO of 10 % and 25 % respectively. These increases correspond to anomalously-high values reported at other Northern Hemisphere sites and are attributed to fires in the Russian Federation. Air mass back trajectory analysis is used to associate the mean enhancements of O3 and CO with trans-Pacific transported or North American air masses relative to the Pacific background. Mean values of the enhancements for March to June in trans-Pacific air masses were 6 ppbv and 16 ppbv for O3 and CO respectively. In summers 2002–2006, higher CO and O3 mixing ratios were almost always observed in North American air masses and this relative enhancement co-varied for each year with the western US and Canada total wildfire area. The greatest enhancements in O3 and CO were seen in 2004, a record year for forest fires in Alaska and the Yukon Territory with average O3 and CO mixing ratios 13 and 43 ppbv above background values.

Germination ecophysiology of the western North American species Osmorhiza depauperata (Apiaceae): implications of preadaptation and phylogenetic niche conservatism in seed dormancy evolution

2004 ◽  
Vol 14 (4) ◽  
pp. 387-394 ◽  
Author(s):  
Jeffrey L. Walck ◽  
Siti N. Hidayati
Keyword(s):  
New Mexico ◽  
North American ◽  
Low Temperatures ◽  
High Elevation ◽  
North American Species ◽  
Niche Conservatism ◽  
Cold Stratification ◽  
Warm Temperature ◽  
Phylogenetic Niche Conservatism ◽  
Morphophysiological Dormancy

Requirements for dormancy break and embryo growth were determined for seeds of the western North American species, Osmorhiza depauperata. Seeds were collected in August 2001 from Sandia Crest (3200 m elevation) and Las Huertas (2300 m), New Mexico (USA). Embryos in fresh seeds were c. 0.6 mm long, and they had to grow to c. 9–10 mm before the radicle emerged from the mericarp. Embryo growth occurred at low temperatures (1 and 5°C), and seeds germinated to high percentages at 1°C during 32 weeks of incubation in the light. No seeds germinated at 5, 15/6, 20/10, 25/15 or 30/15°C during 32 weeks of incubation. Although a 4–18 week warm-temperature (25/15°C) pretreatment increased germination rates at 1°C, it was unnecessary for a high percentage of seeds to germinate. Gibberellic acid (GA3, 10–1000 mg l–1) did not substitute for cold stratification. Seeds from the low-elevation population contained larger embryos and required less time to germinate than those from the high-elevation population. O. depauperata seeds have deep complex morphophysiological dormancy (MPD), which is similar to two other western North American congeners and an Asian congener, but different from two eastern North American congeners. Results from this study suggest that: (1) phylogenetic niche conservatism has played a role in the persistence of deep complex MPD in the three western North American species of Osmorhiza; and (2) the stimulatory effect from a warm pretreatment in species needing only cold stratification for dormancy break is a preadaptation that initiated the development of an absolute warm requirement in species needing both warm and cold stratification.

scholarly journals Interannual variability of ozone and carbon monoxide at the Whistler high elevation site: 2002–2006

2011 ◽  
Vol 11 (6) ◽  
pp. 17621-17664 ◽  
Author(s):  
A. M. Macdonald ◽  
K. G. Anlauf ◽  
W. R. Leaitch ◽  
E. Chan
Keyword(s):  
North American ◽  
Forest Fires ◽  
High Elevation ◽  
Yukon Territory ◽  
Back Trajectory ◽  
Late Winter ◽  
Monthly Means ◽  
Air Masses ◽  
Mixing Ratios ◽  
Western Us

Abstract. In spring 2002, an atmospheric measurement site was established at the peak of Whistler Mountain in British Columbia, Canada to measure trace gases, particle chemistry and physics, and meteorology. This paper uses continuous measurements from March 2002 to December 2006 to investigate the influence of trans-Pacific transport and North American forest fires on both O3 and CO at Whistler. Annual mean mixing ratios of O3 and CO were 41 ppbv (monthly means of 35–48 ppbv) and 145 ppbv (monthly means of 113–177 ppbv) respectively with both species exhibiting an annual cycle of late-winter to early-spring maxima and summer minima. The absence of a broad summer O3 peak differs from previously-reported high altitude sites in the western US. The highest monthly-averaged O3 and CO mixing ratios relative to the 5-year monthly means were seen in fall 2002 and spring 2003 with increased O3 and CO of 10 % and 25 % respectively. These increases correspond to anomalously-high values reported at other Northern Hemisphere sites and are attributed to fires in the Russian Federation. Air mass back trajectory analysis is used to associate the mean enhancements of O3 and CO with trans-Pacific transported or North American air masses relative to the Pacific background. Mean values of the enhancements for March to June were 6 ppbv and 16 ppbv for O3 and CO respectively. In summers 2002–2006, higher CO and O3 mixing ratios were always observed in North American air masses and this relative enhancement co-varied for each year with the western US and Canada total wildfire area. The greatest enhancements in O3 and CO were seen in 2004, a record year for forest fires in Alaska and the Yukon Territory. In August 2004, average O3 and CO mixing ratios were 13 and 44 ppbv above background values.

Phymonotus jacintotopos: A new genus and species of shield-backed katydid (Orthoptera: Tettigoniidae: Tettigoniinae: Nedubini) from the San Jacinto Mountains of California, USA

Zootaxa ◽  
2011 ◽  
Vol 2937 (1) ◽  
pp. 49 ◽  
Author(s):  
DAVID C. LIGHTFOOT ◽  
DAVID B. WEISSMAN ◽  
NORIHIRO UESHIMA
Keyword(s):  
South America ◽  
North American ◽  
Southern California ◽  
New Genus ◽  
High Elevation ◽  
Morphological Features ◽  
South American ◽  
Conifer Forests ◽  
New Genus And Species ◽  
Lower Elevation

We describe the monotypic shield-backed katydid genus Phymonotus and species jacintotopos from the San Jacinto Mountains of southern California, USA. Phymonotus is unique in having an unusually enlarged dome-like pronotum, a distinctive song, and seven additional distinctive morphological features. We believe that Phymonotus is a Pleistocene relic taxon, now endemic to geographically isolated high elevation conifer forests of the San Jacinto Mountains. Nearest relatives Agalothorax and Neduba taxa occur in lower elevation environments throughout the surrounding region. Phymonotus is a member of the katydid tribe Nedubini which has a Gondwanan distribution with additional taxa in Australia and South America (Chile and Argentina). Western North American Nedubini apparently result from a South American dispersal event. We also describe characters newly used for the description and diagnosis of Phymonotus, the dorsal and ventral lobes of the titillators, and the dorsal sclerites of the titillators. We report evidence that Phymonotus males may produce thoracic glandular secretions that are offered to mating females.

Repeats, Returns and Recoveries of North American Migrant Birds Banded in Panama

Bird-Banding ◽  
1966 ◽  
Vol 37 (1) ◽  
pp. 35 ◽  
Author(s):  
Horace Loftin ◽  
David T. Rogers, ◽  
David L. Hicks
Keyword(s):  
North American ◽  
Migrant Birds
Sign in / Sign up

Export Citation Format

Share Document