Ocean-atmospheric interactions, heavy precipitation, and hurricane predictive index (HPI) associated with land-falling Hurricane Irene over the eastern coast of the United States

Abstract. This paper investigates the uncertainties in hourly streamflow ensemble forecasts for an extreme hydrological event using a hydrological model forced with short-range ensemble weather prediction models. A state-of-the art, automated, short-term hydrologic prediction framework was implemented using GIS and a regional scale hydrological model (HEC-HMS). The hydrologic framework was applied to the Hudson River basin ( ∼  36 000 km2) in the United States using gridded precipitation data from the National Centers for Environmental Prediction (NCEP) North American Regional Reanalysis (NARR) and was validated against streamflow observations from the United States Geologic Survey (USGS). Finally, 21 precipitation ensemble members of the latest Global Ensemble Forecast System (GEFS/R) were forced into HEC-HMS to generate a retrospective streamflow ensemble forecast for an extreme hydrological event, Hurricane Irene. The work shows that ensemble stream discharge forecasts provide improved predictions and useful information about associated uncertainties, thus improving the assessment of risks when compared with deterministic forecasts. The uncertainties in weather inputs may result in false warnings and missed river flooding events, reducing the potential to effectively mitigate flood damage. The findings demonstrate how errors in the ensemble median streamflow forecast and time of peak, as well as the ensemble spread (uncertainty) are reduced 48 h pre-event by utilizing the ensemble framework. The methodology and implications of this work benefit efforts of short-term streamflow forecasts at regional scales, notably regarding the peak timing of an extreme hydrologic event when combined with a flood threshold exceedance diagram. Although the modeling framework was implemented on the Hudson River basin, it is flexible and applicable in other parts of the world where atmospheric reanalysis products and streamflow data are available.

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Changes in Observed Daily Precipitation over the United States between 1950–79 and 1980–2009

Journal of Hydrometeorology ◽

10.1175/jhm-d-12-062.1 ◽

2013 ◽

Vol 14 (1) ◽

pp. 105-121 ◽

Cited By ~ 31

Author(s):

R. W. Higgins ◽

V. E. Kousky

Keyword(s):

United States ◽

Great Plains ◽

El Niño ◽

Daily Precipitation ◽

El Nino ◽

Southern Oscillation ◽

Heavy Precipitation ◽

The United States ◽

Enso Cycle ◽

Precipitation Events

Abstract Changes in observed daily precipitation over the conterminous United States between two 30-yr periods (1950–79 and 1980–2009) are examined using a 60-yr daily precipitation analysis obtained from the Climate Prediction Center (CPC) Unified Raingauge Database. Several simple measures are used to characterize the changes, including mean, frequency, intensity, and return period. Seasonality is accounted for by examining each measure for four nonoverlapping seasons. The possible role of the El Niño–Southern Oscillation (ENSO) cycle as an explanation for differences between the two periods is also examined. There have been more light (1 mm ≤ P < 10 mm), moderate (10 mm ≤ P < 25 mm), and heavy (P ≥ 25 mm) daily precipitation events (P) in many regions of the country during the more recent 30-yr period with some of the largest and most spatially coherent increases over the Great Plains and lower Mississippi Valley during autumn and winter. Some regions, such as portions of the Southeast and the Pacific Northwest, have seen decreases, especially during the winter. Increases in multiday heavy precipitation events have been observed in the more recent period, especially over portions of the Great Plains, Great Lakes, and Northeast. These changes are associated with changes in the mean and frequency of daily precipitation during the more recent 30-yr period. Difference patterns are strongly related to the ENSO cycle and are consistent with the stronger El Niño events during the more recent 30-yr period. Return periods for both heavy and light daily precipitation events during 1950–79 are shorter during 1980–2009 at most locations, with some notable regional exceptions.

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Primary Atmospheric Drivers of Pluvial Years in the United States Great Plains

Journal of Hydrometeorology ◽

10.1175/jhm-d-17-0148.1 ◽

2018 ◽

Vol 19 (4) ◽

pp. 643-658 ◽

Cited By ~ 4

Author(s):

Paul X. Flanagan ◽

Jeffrey B. Basara ◽

Jason C. Furtado ◽

Xiangming Xiao

Keyword(s):

United States ◽

Great Plains ◽

Heavy Precipitation ◽

The United States ◽

Precipitation Variability ◽

Northern Great Plains ◽

Southern Great Plains ◽

The Public ◽

Moisture Fluxes ◽

Precipitation Events

Abstract Precipitation variability has increased in recent decades across the Great Plains (GP) of the United States. Drought and its associated drivers have been studied in the GP region; however, periods of excessive precipitation (pluvials) at seasonal to interannual scales have received less attention. This study narrows this knowledge gap with the overall goal of understanding GP precipitation variability during pluvial periods. Through composites of relevant atmospheric variables from the ECMWF twentieth-century reanalysis (ERA-20C), key differences between southern Great Plains (SGP) and northern Great Plains (NGP) pluvial periods are highlighted. The SGP pluvial pattern shows an area of negative height anomalies over the southwestern United States with wind anomalies consistent with frequent synoptic wave passages along a southward-shifted North Pacific jet. The NGP pattern during pluvial periods, by contrast, depicts anomalously low heights in the northwestern United States and an anomalously extended Pacific jet. Analysis of daily heavy precipitation events reveals the key drivers for these pluvial events, namely, an east–west height gradient and associated stronger poleward moisture fluxes. Therefore, the results show that pluvial years over the GP are likely driven by synoptic-scale processes rather than by anomalous seasonal precipitation driven by longer time-scale features. Overall, the results present a possible pathway to predicting the occurrence of pluvial years over the GP and understanding the causes of GP precipitation variability, potentially mitigating the threats of water scarcity and excesses for the public and agricultural sectors.

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On certain limpets and chitons from the deep waters off the eastern coast of the United States

Proceedings of the United States National Museum ◽

10.5479/si.00963801.4-246.400 ◽

1882 ◽

Vol 4 (246) ◽

pp. 400-414 ◽

Cited By ~ 17

Author(s):

William Healey Dall

Keyword(s):

United States ◽

The United States ◽

Eastern Coast ◽

Deep Waters

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XXX.—Salmon (Salmo salar) of the River Moisie (Eastern Canada)

Proceedings of the Royal Society of Edinburgh ◽

10.1017/s0370164600019118 ◽

1926 ◽

Vol 45 (4) ◽

pp. 334-345 ◽

Cited By ~ 1

Author(s):

W. J. M. Menzies

Keyword(s):

United States ◽

Great Britain ◽

Salmo Salar ◽

The United States ◽

European Countries ◽

Eastern Coast ◽

British Isles ◽

Subsequent Growth ◽

Eastern Canada ◽

Made In

Included in the area of distribution of Salmo salar are the western coasts of Europe as far south as the Franco-Spanish border as well as the British Isles and Iceland, and, in addition, the eastern coast of Canada and the United States down to the State of Maine. A very large number of investigations have been made in Great Britain and various European countries, both by marking the fish in order to trace their subsequent growth and movements, and by reading their age and history from the scales. Length calculations from scale measurements have also been made in Scotland, Norway, and Sweden.

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Origin and properties of microseisms from the standpoint of oscillator theory

Bulletin of the Seismological Society of America ◽

10.1785/bssa0550020365 ◽

1965 ◽

Vol 55 (2) ◽

pp. 365-390

Author(s):

Klaus Strobach

Keyword(s):

United States ◽

Love Wave ◽

Wave Motion ◽

Probability Distributions ◽

Source Area ◽

The United States ◽

Eastern Coast ◽

Ann Arbor ◽

Phase Angles ◽

Theoretical Results

Abstract The generally large source area for seawave generated microseisms does not readily allow consideration of these events as unidirectional. Rather, these wave patterns must be due to a complicated interference system, whose properties can be described only by statistics. In this study it is postulated that the generation of microseisms results as the superpositon of the outputs of a large number N of seismic oscillators. These oscillators are randomly distributed both in space and time. This random distribution necessarily implies that the phase angles of incoming waves are randomly distributed too. The statistical properties of the resultant ground motion, outside of the generation area, is investigated theoretically. Special attention is given to the probability distributions of the vertical amplitudes and the horizontal vector amplitudes. Good agreement is found between these theoretical results and the measurements obtained from particle motion diagrams. Additionally, the theoretical results lead to two methods for determination of the microseismic directions of approach. Both of these techniques were applied to the microseismic storm of January 28, 1963. This storm was generated by a well-developed cyclonic system off the east coast of the United States and Canada. Basic data for the study were obtained from the long-period seismograms of 5 stations (Rolla and Florissant, Mo., Bloomington, Ind., Dubuque, Iowa, and Ann Arbor, Mich.). The resulting analysis gave generation areas off the southern coast of Newfoundland and eastern coast of the United States. Further use was made of the theory developed to investigate the character of the microseismic waves. This application showed the microseisms to be composed not only of clear, fundamental mode Rayleigh waves, but that Love wave motion was also present. Surprisingly the proportion of Love wave motion was found to be different at different stations. At Rolla, Florissant and Bloomington, it was predominant, while at Dubuque and Ann Arbor the Rayleigh wave motion was dominant.

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GREAT SHEARWATER(PUFFINUS GRAVIS) MORTALITY EVENTS ALONG THE EASTERN COAST OF THE UNITED STATES

Journal of Wildlife Diseases ◽

10.7589/2012-04-119 ◽

2013 ◽

Vol 49 (2) ◽

pp. 235-245 ◽

Cited By ~ 13

Author(s):

Katherine H. Haman ◽

Terry M. Norton ◽

Robert A. Ronconi ◽

Nicole M. Nemeth ◽

Austen C. Thomas ◽

...

Keyword(s):

United States ◽

The United States ◽

Eastern Coast

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Downstream Weather Impacts Associated with Atmospheric Blocking over the Northeast Pacific

Journal of Climate ◽

10.1175/jcli-3237.1 ◽

2004 ◽

Vol 17 (24) ◽

pp. 4823-4839 ◽

Cited By ~ 63

Author(s):

M. L. Carrera ◽

R. W. Higgins ◽

V. E. Kousky

Keyword(s):

United States ◽

Temperature Distribution ◽

North America ◽

Surface Temperature ◽

Heavy Precipitation ◽

The United States ◽

Boreal Winter ◽

Atmospheric Blocking ◽

Northeast Pacific ◽

Surface Temperature Distribution

Abstract Relationships between atmospheric blocking over the Alaskan region of the northeast Pacific, referred to as Alaskan blocking, and weather extremes over North America during boreal winter 1979–2000 are examined. A total of 37 atmospheric blocking events are identified with durations ranging from 8 to 25 days and a mean duration of 11.3 days. A total of 15.6% of the days during the boreal winter belonged to an Alaskan blocking event. The number of blocked days over the Alaskan region was found to be sensitive to the phase of the ENSO cycle with a reduced (increased) number of blocked days during El Niño (La Niña/neutral) winters. The average number of blocked days during El Niño winters was 12, compared with 31.2 and 27 for neutral and La Niña winters, respectively. The mature Alaskan block possesses characteristics, which are typical of blocking episodes, including the equivalent barotropic structure of the blocking anticyclone, the meridional flow both upstream and downstream of the block, the equatorward shift of the Pacific storm track, downstream development of 500-hPa geopotential height, and sea level pressure anomalies over North America. The surface temperature analysis revealed a significant shift in the daily mean surface temperature distribution during Alaskan blocking toward colder temperatures in the region extending from the Yukon southeastward to the southern plains of the United States, associated with a reduced variance of surface temperatures. Over extreme western Alaska there is a shift in the daily mean surface temperature distribution toward warmer temperatures. The shift toward colder (warmer) daily mean surface temperatures is also accompanied by a shift in the tails of the distribution toward more extreme cold (warm) days in these two regions. During Alaskan blocking, the regions of southern California, the Southwest, and the Intermountain West all possess a higher frequency of heavy precipitation days when compared with the long-term winter climatology. Over the eastern half of the United States, the Ohio Valley and the southeast regions experience a greater percentage of heavy precipitation days during Alaskan blocking.

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An Analogue Approach to Identify Heavy Precipitation Events: Evaluation and Application to CMIP5 Climate Models in the United States

Journal of Climate ◽

10.1175/jcli-d-13-00598.1 ◽

2014 ◽

Vol 27 (15) ◽

pp. 5941-5963 ◽

Cited By ~ 20

Author(s):

Xiang Gao ◽

C. Adam Schlosser ◽

Pingping Xie ◽

Erwan Monier ◽

Dara Entekhabi

Keyword(s):

United States ◽

Large Scale ◽

Heavy Precipitation ◽

The United States ◽

Cmip5 Models ◽

Atmospheric Conditions ◽

South Central ◽

Simulated Precipitation ◽

Analogue Method ◽

Precipitation Events

Abstract An analogue method is presented to detect the occurrence of heavy precipitation events without relying on modeled precipitation. The approach is based on using composites to identify distinct large-scale atmospheric conditions associated with widespread heavy precipitation events across local scales. These composites, exemplified in the south-central, midwestern, and western United States, are derived through the analysis of 27-yr (1979–2005) Climate Prediction Center (CPC) gridded station data and the NASA Modern-Era Retrospective Analysis for Research and Applications (MERRA). Circulation features and moisture plumes associated with heavy precipitation events are examined. The analogues are evaluated against the relevant daily meteorological fields from the MERRA reanalysis and achieve a success rate of around 80% in detecting observed heavy events within one or two days. The method also captures the observed interannual variations of seasonal heavy events with higher correlation and smaller RMSE than MERRA precipitation. When applied to the same 27-yr twentieth-century climate model simulations from Phase 5 of the Coupled Model Intercomparison Project (CMIP5), the analogue method produces a more consistent and less uncertain number of seasonal heavy precipitation events with observation as opposed to using model-simulated precipitation. The analogue method also performs better than model-based precipitation in characterizing the statistics (minimum, lower and upper quartile, median, and maximum) of year-to-year seasonal heavy precipitation days. These results indicate the capability of CMIP5 models to realistically simulate large-scale atmospheric conditions associated with widespread local-scale heavy precipitation events with a credible frequency. Overall, the presented analyses highlight the improved diagnoses of the analogue method against an evaluation that considers modeled precipitation alone to assess heavy precipitation frequency.

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