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At least 253 records · Page 14Linked to original sources
USGS1972

Map showing flood of June 1972 resulting from tropical storm Agnes, Susquehanna River and Yellow Breeches Creek at Steelton, Highspire, and New Cumberland, Pennsylvania

In June 1972, tropical storm Agnes caused severe flooding in Pennsylvania and southern New York. The floods on many major streams were the highest known since the river valleys were settled. Maximum discharges were as much as twice the discharge of a 50-year flood. In central Pennsylvania, large areas in Lock Haven, Mill Hall, Wilkes-Barre, Kingston, Pittston, Harrisburg, and in many smaller communities were inundated to depths of several feet. The extent of flooding shown on the map was delineated by the U.S. Geological Survey from field surveys made soon after the flood.

Pennsylvania↗
USGS1972

Map showing flood of June 1972 resulting from tropical storm Agnes, Susquehanna River at Lemoyne, Pennsylvania

In June 1972, tropical storm Agnes caused severe flooding in Pennsylvania and southern New York. The floods on many major streams were the highest known since the river valleys were settled. Maximum discharges were as much as twice the discharge of a 50-year flood. In central Pennsylvania, large areas in Lock Haven, Mill Hall, Wilkes-Barre, Kingston, Pittston, Harrisburg, and in many smaller communities were inundated to depths of several feet. The extent of flooding shown on the map was delineated by the U.S. Geological Survey from field surveys made soon after the flood.

Pennsylvania↗
USGS1972

Map showing flood of June 1972 resulting from tropical storm Agnes, Bald Eagle and Fishing Creeks at Mill Hall, Pennsylvania

In June 1972, tropical storm Agnes caused severe flooding in Pennsylvania and southern New York. The floods on many major streams were the highest known since the river valleys were settled. Maximum discharges were as much as twice the discharge of a 50-year flood. In central Pennsylvania, large areas in Lock Haven, Mill Hall, Wilkes-Barre, Kingston, Pittston, Harrisburg, and in many smaller communities were inundated to depths of several feet. The extent of flooding shown on the map was delineated by the U.S. Geological Survey from field surveys made soon after the flood.

Pennsylvania↗
USGS1972

Map showing flood of June 1972 resulting from tropical storm Agnes, West Branch Susquehanna River and Bald Eagle Creek at Lock Haven, Pennsylvania

In June 1972, tropical storm Agnes caused severe flooding in Pennsylvania and southern New York. The floods on many major streams were the highest known since the river valleys were settled. Maximum discharges were as much as twice the discharge of a 50-year flood. In central Pennsylvania, large areas in Lock Haven, Mill Hall, Wilkes-Barre, Kingston, Pittston, Harrisburg, and in many smaller communities were inundated to depths of several feet. The extent of flooding shown on the map was delineated by the U.S. Geological Survey from field surveys made soon after the flood.

Pennsylvania↗
USGS1996

Summary of data-collection activities and effects of flooding from tropical storm Alberto in parts of Georgia, Alabama, and Florida, July 1994

Parts of central and southwestern Georgia, southeastern Alabama, and the western panhandle of Florida were devastated by floods resulting from rainfall produced by Tropical Storm Alberto in July 1994. As tributary floodwaters combined and moved downstream in the Flint, Ocmulgee, and Choctawhatchee Rivers, peak discharges exceeded the 100-year flood discharges along most stream reaches. Along the Flint River, the 100-year flood stage was exceeded at Montezuma by 3.7 ft; at Albany, by 5.1 ft; at Newton, by 3.9 ft; and at Bainbridge by 2.2 ft. Along the Ocmulgee River, the 100-year flood was exceeded at Juliette, by 5.4 ft; at Macon, by 2.2 ft; and at Hawkinsville by 3.9 ft. Peak discharges exceeded the 100-year flood discharges along the Choctawhatchee River from Newton, Ala., to Bruce, Fla. Discharge measurements were made at many gaging stations throughout the area of flooding. Streamflow velocities are obtained during the process of making the discharge measurement. Velocity data are given for selected gaging stations on two streams in Georgia. Scour around pier and abutment foundations caused settling or washout at most bridge failures. Scour mechanisms at these bridges include local scour, contraction scour, and scour plus bank instability of the general stream reach where the bridge is located. Eighteen feet of predominantly contraction scour was measured during the flood at the U.S. Highway 82 crossing of Flint River at Albany, Ga.

Alabama, Florida, Georgia↗
USGS2012

Effects of earthworms on slopewash, surface runoff, and fine-litter transport on a humid-tropical forested hillslope in eastern Puerto Rico: Chapter G in Water quality and landscape processes of four watersheds in eastern Puerto Rico

Rainfall, slopewash (the erosion of soil particles), surface runoff, and fine-litter transport were measured in tropical wet forest on a hillslope in the Luquillo Experimental Forest, Puerto Rico, from February 1998 until April 2000. Slopewash data were collected using Gerlach troughs at eight plots, each 2 square meters in area. Earthworms were excluded by electroshocking from four randomly selected plots. The other four (control) plots were undisturbed. During the experiment, earthworm population in the electroshocked plots was reduced by 91 percent. At the end of the experiment, the electroshocked plots had 13 percent of earthworms by count and 6 percent by biomass as compared with the control plots. Rainfall during the sampling period (793 days) was 9,143 millimeters. Mean and maximum rainfall by sampling period (mean of 16 days) were 189 and 563 millimeters, respectively. Surface runoff averaged 0.6 millimeters and 1.2 millimeters by sampling period for the control and experimental plots, equal to 0.25 and 0.48 percent of mean rainfall, respectively. Disturbance of the soil environment by removal of earthworms doubled runoff and increased the transport (erosion) of soil and organic material by a factor of 4.4. When earthworms were removed, the erosion of mineral soil (soil mass left after ashing) and the transport of fine litter were increased by a factor of 5.3 and 3.4, respectively. It is assumed that increased runoff is a function of reduced soil porosity, resulting from decreased burrowing and reworking of the soil in the absence of earthworms. The background, or undisturbed, downslope transport of soil, as determined from the control plots, was 51 kilograms per hectare and the "disturbance" rate, determined from the experimental plots, was 261 kilograms per hectare. The background rate for downslope transport of fine litter was 71 kilograms per hectare and the disturbance rate was 246 kilograms per hectare. Data from this study indicate that the reduction in soil macrofauna population, in this case, earthworms, plays a key role in increasing runoff and soil erosion and, therefore, has important implications for forest and water management.

Luquillo Experimental Forest↗
USGS2014

Flood inundation maps and water-surface profiles for tropical storm Irene and selected annual exceedance probability floods for Flint Brook and the Third Branch White River in Roxbury, Vermont

Flint Brook, a tributary to the Third Branch White River in Roxbury, Vermont, has a history of flooding the Vermont Fish and Wildlife Department’s Roxbury Fish Culture Station (the hatchery) and surrounding infrastructure. Flooding resulting from tropical storm Irene on August 28–29, 2011, caused widespread destruction in the region, including extensive and costly damages to the State-owned hatchery and the transportation infrastructure in the Town of Roxbury, Vermont. Sections of State Route 12A were washed out, and several bridges and culverts on Oxbow Road, Thurston Hill Road, and the New England Central Railroad in Roxbury were heavily damaged. Record high peak-discharge estimates of 2,140 cubic feet per second (ft 3 /s) and 4,320 ft 3 /s were calculated for Flint Brook at its confluence with the Third Branch White River and for the Third Branch White River at about 350 feet (ft) downstream from the hatchery, respectively. The annual exceedance probabilities (AEPs) of the peak discharges for Flint Brook and the Third Branch White River were less than 0.2 percent (less than a one in 500 chance of occurring in a given year). Hydrologic and hydraulic analyses of Flint Brook and the Third Branch White River were done to investigate flooding at the hatchery in Roxbury and support efforts by the Federal Emergency Management Agency to assist State and local mitigation and reconstruction efforts. During the August 2011 flood, the majority of flow from Flint Brook (97 percent or 2,070 ft 3 /s) diverged from its primary watercourse due to a retaining wall failure immediately upstream of Oxbow Road and inundated the hatchery. Although a minor amount of flow from the Third Branch White River could have overtopped State Route 12A and spilled into the hatchery, the Third Branch White River did not cause flood damages or exacerbate flooding at the hatchery during the August 2011 flood. The Third Branch White River which flows adjacent to the hatchery does not flood the hatchery for the 10-, 2-, 1, or 0.2-percent annual exceedance probabilities. The simulated water-surface elevations for August 2011 flood equal the elevations of State Route 12A about 500 ft downstream of Thurston Hill Road adjacent to the troughs between the rearing ponds. Four flood mitigation alternatives being considered by the Vermont Agency of Transportation to improve the hydraulic performance of Flint Brook and reduce the risk of flooding at the hatchery include: (A) no changes to the infrastructure or existing alignment of Flint Brook (existing conditions [2014]), (B) structural changes to the bridges and the existing retaining wall along Flint Brook, (C) realignment of Flint Brook to flow along the south side of Oxbow Road to accommodate larger stream discharges, and (D) a diversion channel for flows greater than 1-percent annual exceedance probability. Although the 10-, 2-, and 1-percent AEP floods do not flood the hatchery under alternative A (no changes to the infrastructure), the 0.2-percent AEP flow still poses a flooding threat to the hatchery because flow will continue to overtop the existing retaining wall and flood the hatchery. Under the other mitigation alternatives (B, C, and D) that include some variation of structural changes to bridges, a retaining wall, and (or) channel, the peak discharges for the 10-, 2-, 1-, and 0.2-percent annual exceedance probabilities do not flood the hatchery. Water-surface profiles and flood inundation maps of the August 2011 flood and the 10-, 2-, 1-, and 0.2-percent AEPs for four mitigation alternatives were developed for Flint Brook and the Third Branch White River in the vicinity of the hatchery and can be used by the Federal, State, and local agencies to better understand the potential for future flooding at the hatchery.

Vermont↗
USGS1994

Water quality of the Apalachicola-Chattahoochee-Flint and Ocmulgee River Basins related to flooding from Tropical Storm Alberto; pesticides in urban and agricultural watersheds; and nitrate and pesticides in ground water, Georgia, Alabama, and Florida

This report presents preliminary water-quality information from three studies that are part of the National Water-Quality Assessment (NAWQA) Program in the Apalachicola-Chattahoochee-Flint (ACF) River basin and the adjacent Ocmulgee River basin. During the period July 3-7, 1994, heavy rainfall from tropical storm Alberto caused record flooding on the Ocmulgee and Flint Rivers and several of their tributaries. Much of the nitrogen load transported during the flooding was as organic nitrogen generally derived from organic detritus, rather than nitrate derived from other sources, such as fertilizer. More than half the mean annual loads of total phosphorus and organic nitrogen were trans- ported in the Flint and Ocmulgee Rivers during the flood. Fourteen herbicides, five insecticides, and one fungicide were detected in floodwaters of the Ocmulgee, Flint, and Apalachicola Rivers. In a second study, water samples were collected at nearly weekly intervals from March 1993 through April 1994 from one urban and two agricultural watersheds in the ACF River basin, and analyzed for 84 commonly used pesticides. More pesticides were detected and at generally higher concentrations in water from the urban watershed than the agricultural water- sheds, and a greater number of pesticides were persistent throughout much of the year in the urban watershed. Simazine exceeded U.S. Environmental Protection Agency (EPA) drinking-water standards in one of 57 samples from the urban watershed. In a third study, 38 wells were installed in surficial aquifers adjacent to and downgradient of farm fields within agricultural areas in the southern ACF River basin. Even though regional aquifers are generally used for irrigation and domestic- and public-water supplies, degradation of water quality in the surficial aquifers serves as an early warning of potential contamination of regional aquifers. Nitrate concentrations were less than 3 mg/L as N (indicating minimal effect of human activities) in water from about two-thirds of the wells. Water from the remaining wells had elevated nitrate con- centrations, probably the result of human activity. Nitrate concentrations in two of these wells exceeded EPA drinking-water standards. Water samples from eight wells had pesticide concentrations above method detection limits. With the exception of two samples for shallow ground-water wells and one surface-water sample from the urban watershed, concentrations of nitrate nitrogen and detected pesticides were below EPA standards and guidelines for drinking water. However, concentrations of the insecticides chlorpyrifos, carbaryl, and diazinon in the surface-water samples approached or exceeded guidelines for protection of aquatic life.

Alabama, Florida, Georgia↗
USGS2004

Tropical Archaea: Diversity associated with the surface microlayer of corals

Recent 16S rDNA studies have focused on detecting uncultivated bacteria associated with Caribbean reef corals in an effort to address the ecological roles of coral-associated microbes. Reports of Archaea associated with fishes and marine invertebrates raised the question of whether Archaea might also be part of the coral-associated microbial community. DNA analysis of mucus from 3 reef-building species of Caribbean corals, Montastraea annularis complex, Diploria strigosa and D. labyrinthiformis in the US Virgin Islands yielded 34 groups of archaeal 16S ribotypes (defined at the level of 97% similarity). The majority (75%) was most closely matched by BLAST searches to sequences derived from marine water column samples, whereas the remaining ribotypes were most similar to sequences isolated from anoxic environments (15%) and hydrothermal vents (9%). Unlike previous 16S studies of coral-associated Bacteria, the results do not suggest specific associations between particular archaeal sequences and individual coral species. Marine Archaea (Groups I, II and III) in addition to Thermoplasma -like, methanogen, and marine benthic crenarchaeote phylotypes, were detected in the mucus of tropical corals. The finding of sequences from coral-associated Archaea that are closely related to strict and facultative anaerobes, as well as to uncultivated Archaea from other types of anoxic environments, suggests that anaerobic micro-niches may exist in coral mucus layers. Archaea, with their unique biogeochemical capabilities, broaden the scope of possible interactions between corals and their associated microbial communities.

Marine Ecology Progress Series↗
USGS2019

Hysteretic response of solutes and turbidity at the event scale across forested tropical montane watersheds

Concentration-discharge relationships are a key tool for understanding the sourcing and transport of material from watersheds to fluvial networks. Storm events in particular provide insight into variability in the sources of solutes and sediment within watersheds, and the hydrologic pathways that connect hillslope to stream channel. Here we examine high-frequency sensor-based specific conductance and turbidity data from multiple storm events across two watersheds (Quebrada Sonadora and Rio Icacos) with different lithology in the Luquillo Mountains of Puerto Rico, a forested tropical ecosystem. Our analyses include Hurricane Maria, a category 5 hurricane. To analyze hysteresis, we used a recently developed set of metrics to describe and quantify storm events including the hysteresis index (HI), which describes the directionality of hysteresis loops, and the flushing index (FI), which can be used to infer whether the mobilization of material is source or transport limited. We also examine the role of antecedent discharge to predict hysteretic behavior during storms. Overall, specific conductance and turbidity showed contrasting responses to storms. The hysteretic behavior of specific conductance was very similar across sites, displaying clockwise hysteresis and a negative flushing index indicating proximal sources of solutes and consistent source limitation. In contrast, the directionality of turbidity hysteresis was significantly different between watersheds, although both had strong flushing behavior indicative of transport limitation. Overall, models that included antecedent discharge did not perform any better than models with peak discharge alone, suggesting that the magnitude and trajectory of an individual event was the strongest driver of material flux and hysteretic behavior. Hurricane Maria produced unique hysteresis metrics within both watersheds, indicating a distinctive response to this major hydrological event. The similarity in response of specific conductance to storms suggests that solute sources and pathways are similar in the two watersheds. The divergence in behavior for turbidity suggests that sources and pathways of particulate matter vary between the two watersheds. The use of high-frequency sensor data allows the quantification of storm events while index-based metrics of hysteresis allow for the direct comparison of complex storm events across a heterogeneous landscape and variable flow conditions.

Luquillo Mountains↗
USGS2018

The effects of tropical cyclone-generated deposition on the sustainability of the Pearl River marsh, Louisiana: The importance of the geologic framework

Shoreline retreat is a tremendously important issue along the coast of the northern Gulf of Mexico, especially in Louisiana. Although this marine transgression results from a variety of causes, the crucial factor is the difference between marsh surface elevation and rising sea levels. In most cases, the primary cause of a marsh's inability to keep up with sea level is the lack of input of inorganic material. Although tropical cyclones provide an important source of such sediment, little effort has been made to determine the point of origin of the deposited material. In this study we use sedimentary, geochemical and biogeochemical data to identify the bed of the Pearl River and/or Lake Borgne as the source of a ~5 cm thick clastic layer deposited on the surface of the Pearl River marsh on the Louisiana/Mississippi border. Radiochemical chronologies and sedimentary evidence indicate that this layer was associated with the passage of Hurricane Katrina in 2005. As this material would otherwise have been lost to the system, this deposition indicates a net gain to marsh surface elevation. Accretion rates, determined from 137Cs and 14C profiles and the use of the Katrina layer as a stratigraphic marker, indicate that short-term (~50 years) rates are as much as an order of magnitude higher than the long- term (1000s of years) rates. We suggest that the marsh's geologic setting in an incised river valley with steep vertical constraints and a large fluvial discharge, promotes rapid accretion rates, with rates accelerating as the sea moves inland, due to extended hydroperiods and the input of clastic material from both the marine and terrestrial sides. These rates are especially large when compared to accretion occurring in the more common open marshes fringing the Gulf that lack fluvial input. The difference is particularly large when related to marsh recovery/regrowth following the deposition of thick hurricane-generated clastic layers. Given the number of similar incised river valleys along the Gulf Coast, we believe that understanding the processes controlling marsh accretion in such environments is essential in evaluating marsh sustainability on a regional basis.

Louisiana↗
USGS2026

Advancing ecosystem recovery with diverse species plantings in tropical forest restoration

Tropical forest restoration has increased in the past decades, with possible advancements given the UN declaration of the “Decade of Ecosystem Restoration”. However, robust assessments to compare ecosystem functions among restored forest stages are essential. We evaluated 13 actively restored forest stands ranging from 3 to 21 years of age and compared measures of forest biodiversity, structure, and ecosystem function to four 70+ year old “reference” stands that serve as restoration “targets” in the study region of the Premontane wet forest of Costa Rica. The restored stands were planted with an average of 13 tree species on abandoned pastures that were fallow for at least two years. Sixteen tree-stand attributes and six ecosystem function estimates were assessed, including: annual biomass (C) accumulation, N-fixation potential, threatened species conservation, and the provision of avian frugivore forage, insect habitat, and insect pollination. Using Principal Component Analysis, linear modeling, and Mahalanobis distance analyses, we learned that planting a diversity of tree species sets the stage for forest recovery at early restoration ages, with an inflection point at 15 years towards older reference forest characteristics and functions. Given that all restoration ages provided tree diversity and some level of ecosystem functions, the value of all restored stands in the landscape is notable. The assessment methods are easily employed, thereby providing an accessible tool to restoration practitioners.

Monteverde↗
USGS2017

Analyzing cloud base at local and regional scales to understand tropical montane cloud forest vulnerability to climate change

The degree to which cloud immersion provides water in addition to rainfall, suppresses transpiration, and sustains tropical montane cloud forests (TMCFs) during rainless periods is not well understood. Climate and land use changes represent a threat to these forests if cloud base altitude rises as a result of regional warming or deforestation. To establish a baseline for quantifying future changes in cloud base, we installed a ceilometer at 100 m altitude in the forest upwind of the TMCF that occupies an altitude range from ∼ 600 m to the peaks at 1100 m in the Luquillo Mountains of eastern Puerto Rico. Airport Automated Surface Observing System (ASOS) ceilometer data, radiosonde data, and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite data were obtained to investigate seasonal cloud base dynamics, altitude of the trade-wind inversion (TWI), and typical cloud thickness for the surrounding Caribbean region. Cloud base is rarely quantified near mountains, so these results represent a first look at seasonal and diurnal cloud base dynamics for the TMCF. From May 2013 to August 2016, cloud base was lowest during the midsummer dry season, and cloud bases were lower than the mountaintops as often in the winter dry season as in the wet seasons. The lowest cloud bases most frequently occurred at higher elevation than 600 m, from 740 to 964 m. The Luquillo forest low cloud base altitudes were higher than six other sites in the Caribbean by ∼ 200–600 m, highlighting the importance of site selection to measure topographic influence on cloud height. Proximity to the oceanic cloud system where shallow cumulus clouds are seasonally invariant in altitude and cover, along with local trade-wind orographic lifting and cloud formation, may explain the dry season low clouds. The results indicate that climate change threats to low-elevation TMCFs are not limited to the dry season; changes in synoptic-scale weather patterns that increase frequency of drought periods during the wet seasons (periods of higher cloud base) may also impact ecosystem health.

Atmospheric Chemistry and Physics↗
USGS2025

Pluvial and potential compound flooding in a coupled coastal modeling framework: New York City during post-tropical Cyclone Ida (2021)

Many coastal urban areas are prone to extreme pluvial flooding due to limitations in stormwater system capacity, with the additional potential for flooding compounded by storm surge, tides, and waves. Understanding and simulating these processes can improve prediction and flood risk management. Here, we adapt the Coupled Ocean–Atmosphere–Wave–Sediment Transport modeling framework (COAWST) to simulate pluvial flooding from post-tropical Cyclone Ida (2021) in the Jamaica Bay watershed of New York City (NYC). We modify the model to capture the volumetric effects of rainfall and parameterize soil infiltration and a stormwater conveyance system as the drainage rate. We generate a spatially continuous flood map of Ida with a root-mean-square error (RMSE) of 20 cm when compared to high-water marks, useful for understanding Ida's impacts and subsequent mitigation planning. Results show that over 23 km 2 and 4621 buildings were flooded deeper than 0.3 m during Ida. Sensitivity analyses are used to study the broader risk from events like Ida (pluvial flooding) as well as potential compound (pluvial–coastal) flooding. Spatial shifting of the storm track within a typical 12 h forecast uncertainty reveals a worst-case scenario that increases this flooded area to 62 km 2 (5907 buildings). Shifting Ida's rainfall to coincide with high tide increases this flooded area by 1 km 2 , a relatively small change due to the lack of significant storm surge. The application of COAWST to this storm event addresses a broader goal of developing the capability to model compound pluvial–coastal flooding by simultaneously representing coastal storm processes such as rain, tide, waves, erosion, and atmosphere–wave–ocean interactions. The sensitivity analysis results underscore the need for detailed flood risk assessments, showing that Ida, already NYC's worst rain event, could have been even more devastating with slight shifts in the storm track.

New York↗
USGS1996

Weights, hematology and serum chemistry of seven species of free-ranging tropical pelagic seabirds

I established reference values for weight, hematology, and serum chemistry for seven species of free-ranging Hawaiian tropical pelagic seabirds comprising three orders (Procellariiformes, Pelecaniformes, Charadriiformes) and six families (Procellariidae, Phaethontidae, Diomedeidae, Sulidae, Fregatidae, and Laridae). Species examined included 84 Hawaiian dark-rumped petrels ( Pterodoma phaeopygia ), 90 wedge-tailed shearwaters ( Puffinus pacificus ), 151 Laysan albatrosses ( Diomedea immutabilis ), 69 red-footed boobies ( Sula sula ), 154 red-tailed tropicbirds ( Phaeton rubricauda ), 90 great frigatebirds ( Fregata minor ), and 72 sooty terns ( Sterna fuscata ). Hematocrit, total plasma solids, total and differential white cell counts, serum glucose, calcium, phosphorus, uric acid, total protein, albumin, globulin, aspartate aminotransferase and creatinine phosphokinase were analyzed. Among and within species, hematology and chemistry values varied with age, sex, season, and island of collection. Despite this variation, order-wide trends were observed.

Hawai'i↗
USGS1997

Flooding in southeastern United States from tropical storm Alberto, July 1994

In July 1994, parts of central and southwestern Georgia, southeastern Alabama, and the western panhandle of Florida were devastated by floods resulting from rainfall produced by Tropical Storm Alberto. Entire communities were inundated by flood waters as numerous streams reached peak stages and discharges far greater than previous floods in the Flint, Ocmulgee, and Choctawhatchee River basins. The flooding resulted in 33 deaths in towns and small communities along or near the overflowing streams. President Clinton declared 78 counties as Federal disaster areas: 55 in Georgia, 10 in Alabama, and 13 in Florida. The Flint River and Ocmulgee River basins in Georgia experienced floods that exceeded the 100-year recurrence interval discharge along almost their entire lengths. Travel was disrupted as railroad and highway bridges and culverts were overtopped an, in many cases, washed out. Total flood damages to public and private property were estimated at nearly $1 billion dollars. The destruction caused by this storm serves to emphasize the high cost imposed upon life and property by flood disasters; and thus, highlight the importance of preparing for, monitoring, and documenting such occurrences.

Southeastern United States↗
USGS1995

Flooding in southeastern United States from tropical storm Alberto, July 1994

In July 1994, parts of Georgia, Alabama and Florida were devastated by floods resulting from rainfall produced by Tropical Storm Alberto. The flooding resulted in 33 human deaths in towns and small communities or near swollen streams. Total damages to public and private property were estimated at nearly $1 billion dollars. This article highlights severe stream flooding resulting from Alberto and describes U.S. Geological Survey (USGS) efforts to document this event and provide information to those who need it.

Conference Paper↗
USGS1998

Landfalling Tropical Cyclones: Forecast Problems and Associated Research Opportunities

The Fifth Prospectus Development Team of the U.S. Weather Research Program was charged to identify and delineate emerging research opportunities relevant to the prediction of local weather, flooding, and coastal ocean currents associated with landfalling U.S. hurricanes specifically, and tropical cyclones in general. Central to this theme are basic and applied research topics, including rapid intensity change, initialization of and parameterization in dynamical models, coupling of atmospheric and oceanic models, quantitative use of satellite information, and mobile observing strategies to acquire observations to evaluate and validate predictive models. To improve the necessary understanding of physical processes and provide the initial conditions for realistic predictions, a focused, comprehensive mobile observing system in a translating storm-coordinate system is required. Given the development of proven instrumentation and improvement of existing systems, three-dimensional atmospheric and oceanic datasets need to be acquired whenever major hurricanes threaten the United States. The spatial context of these focused three-dimensional datasets over the storm scales is provided by satellites, aircraft, expendable probes released from aircraft, and coastal (both fixed and mobile), moored, and drifting surface platforms. To take full advantage of these new observations, techniques need to be developed to objectively analyze these observations, and initialize models aimed at improving prediction of hurricane track and intensity from global-scale to mesoscale dynamical models. Multinested models allow prediction of all scales from the global, which determine long- term hurricane motion to the convective scale, which affect intensity. Development of an integrated analysis and model forecast system optimizing the use of three-dimensional observations and providing the necessary forecast skill on all relevant spatial scales is required. Detailed diagnostic analyses of these datasets will lead to improved understanding of the physical processes of hurricane motion, intensity change, the atmospheric and oceanic boundary layers, and the air- sea coupling mechanisms. The ultimate aim of this effort is the construction of real-time analyses of storm surge, winds, and rain, prior to and during landfall, to improve warnings and provide local officials with the comprehensive information required for recovery efforts in the hardest hit areas as quickly as possible.

Bulletin of the American Meteorological Society↗