The butterflies of the eastern United States and Canada : with special reference to New England / By Samuel Hubbard Scudder.

AbstractThe various lobes and segments of the southern periphery of the Laurentide ice sheet reached their maximum extension at different times between 21,000 and 14,000 yr ago, but the CLIMAP date of 18,000 yr ago is taken as a reference level to review the distribution of major vegetational formations in central and eastern United States. Tundra was apparently confined to a narrow belt peripheral to the ice margin only in the Minnesota area and from northern Pennsylvania to New England, with extensions down the crest of the Appalachian Highlands at least as far as Maryland. Some areas south of the Great Lakes may later have been marked by treeless vegetation briefly as the ice retreated. The boreal forest to the south in the central United States was dominated by spruce; the jack pine that had prevailed during previous times was apparently eliminated by the time the ice reached its maximum. In the Appalachian Highlands and the Atlantic Coastal Plain, however, jack pine occurred along with spruce, which decreased in importance southward. The southern limit of the boreal forest in the Southeast was perhaps somewhere in southern Georgia and Alabama. Oak and other temperate deciduous trees were minor components of the boreal coniferous forests especially in the southern Appalacchians, but there is no evidence yet in the southeastern states for a relic mixed mesophytic forest 18,000 yr ago similar to the rich modern deciduous forests of the region, except possibly in the Lower Mississippi Valley. The climate in much of the Southeast was apparently dry as well as cool at that time; in Florida oak/pine scrub and prairie-like openings prevailed, and all but the deepest lakes dried up.

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Field book of insects : with special reference to those of north-eastern United States, aiming to answer common questions /

10.5962/bhl.title.51175 ◽

1921 ◽

Cited By ~ 2

Author(s):

Frank E. Lutz

Keyword(s):

United States ◽

Special Reference ◽

Eastern United States ◽

North Eastern

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The continental margin of the eastern United States

Canadian Journal of Earth Sciences ◽

10.1139/e68-097 ◽

1968 ◽

Vol 5 (4) ◽

pp. 993-1010 ◽

Cited By ~ 57

Author(s):

Charles L. Drake ◽

John I. Ewing ◽

Henry Stockard

Keyword(s):

United States ◽

New England ◽

Continental Margin ◽

Magnetic Measurements ◽

Large Body ◽

Ocean Basin ◽

Eastern United States ◽

Geological Data ◽

The Bahamas ◽

Reflection And Refraction

Geophysical and geological data of many types are now available from the continental margin of the eastern United States. These include seismic reflection and refraction data, gravity and magnetic measurements, cores of sediments and dredge hauls of rocks, underwater photographs, echo sounding data, and a large body of surface and subsurface geological data from the adjacent land.Major differences in the sedimentary pattern and sedimentary types occur from north to south and reflect not only source differences but also differences in means of transport and deposition. The data indicate a continuity of structure from Newfoundland to the Bahamas, interrupted only by the Kelvin-New England seamount group and associated structures ashore. They suggest that the ocean basin west of Bermuda is at least as old as Paleozoic.

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Regional site response and uppermost mantle seismic structure of central and eastern united states

10.32469/10355/72232 ◽

2019 ◽

Author(s):

◽

Rayan Yassminh

Keyword(s):

United States ◽

New England ◽

Velocity Ratio ◽

Site Amplification ◽

P Wave ◽

Seismic Structure ◽

Eastern United States ◽

Uppermost Mantle ◽

Pn Velocity ◽

Mantle Temperature

This dissertation examines seismological data from regional earthquake sources in order to examine the seismological character of the crust and uppermost mantle in central and eastern United States. Firstly, site amplification of regional highfrequency Lg seismic phases is estimate ed using a Reverse-Two Station (RTS) method. RTS results show topography and sediment thickness are likely to affect amplification and both factors likely frequency-dependent. There is a negative correlation between the RTS-measured amplification and shallow shear-wave velocity. It appears that both regional topography (i.e., long-wavelength topography) and deeper subsurface seismic structures (basins and sediments) have a large impact on site amplification. Subsequently, Pn and Sn travel time tomography is used to estimate the upper most mantle P-wave (Pn) velocity, S-wave (Sn) velocity, and the velocity ratio (VPn/VSn). In addition to velocity, effective attenuation of Sn phase (Q[superscript -1]sn) is also measured. The result shows regions of high velocity such as southern Georgia, eastern South Carolina and NMSZ and low Q[subscript Sn] values. The V[subscript Pn]/V[subscript Sn] ratio shows values higher than the average in regions such as the Mississippi Embayment, New England, and south Appalachian. V[subscript Pn]/V[subscript Sn] ratios are lower than the average in regions such as northwestern CEUS, South Georgia and eastern Texas. We estimated the uppermost mantle temperature by applying a constrained grid-search algorithm includes the observed V[subscript Sn], V[subscript Pn] and Q[subscript Sn] with the calculated velocities of specific compositional models. The uppermost mantle temperature result, [about]300-500C, beneath the northern mid-continent, and the highest temperature, 1100 C, beneath New England

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Winter Weather Regimes in the Northeast United States

Journal of Climate ◽

10.1175/jcli-d-15-0274.1 ◽

2016 ◽

Vol 29 (8) ◽

pp. 2963-2980 ◽

Cited By ~ 26

Author(s):

Christopher D. Roller ◽

Jian-Hua Qian ◽

Laurie Agel ◽

Mathew Barlow ◽

Vincent Moron

Keyword(s):

United States ◽

Great Lakes ◽

New England ◽

East Coast ◽

Storm Tracks ◽

Eastern United States ◽

Western Atlantic ◽

Weather Patterns ◽

Precipitation Anomalies ◽

The U.S

Abstract The method of k-means cluster analysis is applied to U.S. wintertime daily 850-hPa winds across the Northeast. The resulting weather patterns are analyzed in terms of duration, station, gridded precipitation, storm tracks, and climate teleconnections. Five distinct weather patterns are identified. Weather type (WT) 1 is characterized by a ridge over the western Atlantic and positive precipitation anomalies as far north as the Great Lakes; WT2, by a trough along the eastern United States and positive precipitation anomalies into southern New England; WT3, by a trough over the western Atlantic and negative precipitation anomalies along much of the U.S. East Coast; WT4, by a trough east of Newfoundland and negative precipitation anomalies along parts of the U.S. East Coast; and WT5, by a broad, shallow trough over southeastern Canada and negative precipitation anomalies over the entire U.S. East Coast. WT5 and WT1 are the most persistent, while WT2 typically progresses quickly to WT3 and then to WT4. Based on mean station precipitation in the northeastern United States, most precipitation occurs in WT2 and WT3, with the least in WT1 and WT4. Extreme precipitation occurs most frequently in WT2. Storm tracks show that WT2 and WT3 are associated with coastal storms, while WT2 is also associated with Great Lakes storms. Teleconnections are linked with a change in WT frequency by more than a factor of 2 in several cases: for the North Atlantic Oscillation (NAO) in WT1 and WT4 and for the Pacific–North American (PNA) pattern in WT1 and WT3.

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Variability in Wind Energy Generation across the Contiguous United States

Journal of Applied Meteorology and Climatology ◽

10.1175/jamc-d-20-0162.1 ◽

2020 ◽

Vol 59 (12) ◽

pp. 2021-2039

Author(s):

S. C. Pryor ◽

F.W. Letson ◽

R. J. Barthelmie

Keyword(s):

United States ◽

Wind Energy ◽

New England ◽

Wind Turbine ◽

Grid Cell ◽

Wind Farms ◽

Optimal Strategies ◽

Power Production ◽

The United States ◽

Eastern United States

AbstractERA5 provides high-resolution, high-quality hourly wind speeds at 100 m and is a unique resource for quantifying temporal variability in likely wind-derived power production across the United States. Gross capacity factors (CF) in seven independent system operators (ISOs) are estimated using the location and rated power of each wind turbine, a simplified power curve, and ERA5 output from 1979 to 2018. Excluding the California ISO, the marginal probability of a calm (zero power production) is less than 0.1 in any ERA5 grid cell. When a calm occurs, the mean co-occurrence across wind-turbine-containing grid cells ranges from 0.38 to 0.39 for ISOs in the Midwest and central plains [Midcontinent (or Midwest) ISO (MISO), Southwest Power Pool (SPP), and the Electric Reliability Council of Texas (ERCOT) region], increasing to 0.54–0.58 for ISOs in the eastern United States [Pennsylvania–New Jersey–Maryland interconnection (PJM), New York ISO (NYISO), and New England ISO (NEISO)]. Periods with low gross CF have a median duration of ≤6 h, except in California, and are most likely during summer. Gross CF exhibit highest variance at periods of 1 day in ERCOT and SPP; on synoptic scales in MISO, NEISO, and NYISO; and on interannual time scales in PJM. This implies differences in optimal strategies for ensuring resilience of supply. Theoretical scenarios show adding wind energy capacity near existing wind farms is advantageous even in areas with high existing installed capacity (IC), while expanding into areas with lower IC is more beneficial to reducing ramps and the probability of gross CF falling below 20%. These results emphasize the benefits of large balancing areas and aggregation in reducing wind power variability and the likelihood of wind droughts.

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