Christopher W. Brown

University of Maryland, College Park | UMD, UMCP, University of Maryland College Park · Earth System Science Interdisciplinary Center

Aquaculturists, local beach managers, and other stakeholders require forecasts of harmful biotic events, so they can assess and respond to health threats when harmful algal blooms (HABs) are present. Based on this need, we are developing empirical habitat suitability models for a variety of Chesapeake Bay HABs to forecast their occurrence based on...

Environmental conditions are important drivers in regulating the distribution pattern of phytoplankton composition in the world's oceans. We constructed models that predict pico-, nano-and micro-phytoplankton size classes and assessed the impact of separately including sea surface temperature (SST) and estimates of light level in the surface mixed-...

First International Operational Satellite Oceanography Symposium; College Park, Maryland, 18–20 June 2019

Bio-optical database of spectral light attenuation, scattering, absorption, and backscattering properties of 29 species of cultured marine plankton representing 12 classes and one marine heterotrophic bacterium.

Ocean ecosystems are subject to a multitude of stressors, including changes in ocean physics and biogeochemistry, and direct anthropogenic influences. Implementation of protective and adaptive measures for ocean ecosystems requires a combination of ocean observations with analysis and prediction tools. These can guide assessments of the current sta...

Historical understanding of marine biological dynamics has been limited by sparse in situ observations and the fact that dedicated ocean color satellite remote sensing only began in 1997. From these observations, it has become clear that physical oceanography controls biological variability over seasonal to interannual time scales. To quantify how...

The Chesapeake Bay is a valuable recreational, ecological and economic resource that is subject to environmental hazards, such as harmful algal bloom (HAB) and hypoxia, which can degrade the Bay’s health and jeopardize the viability of this important natural resource. As a step toward developing the capability to forecast such hazards, a biogeochem...

Improving forecasts of salinity from coastal hydrodynamic models would further our predictive capacity of physical, chemical, and biological processes in the coastal ocean. However, salinity is difficult to estimate in coastal and estuarine waters at the temporal and spatial resolution required. Retrieving sea surface salinity (SSS) using satellite...

The Galápagos is a flourishing yet fragile ecosystem whose health is particularly sensitive to regional and global climate variations. The distribution of several species, including the Galápagos Penguin, is intimately tied to upwelling of cold, nutrient-rich water along the western shores of the archipelago. Here we show, using reliable, high-reso...

Blooms of the coccolithophore Emiliania huxleyi were detected around the world from 1982 through 2006 using Advanced Very High Resolution Radiometer (AVHRR) remote sensing reflectances. The annually averaged surface area of these blooms has decreased over the past 25 years in regions where E. huxleyi blooms are most prevalent - the Bering Sea, the...

National Oceanic and Atmospheric Administration (NOAA) is uniquely positioned to apply its considerable forecasting capabilities and experience toward predicting the response of ecosystems and their components to environmental changes. With the recent frequency and severity of episodic ecosystem events and the associated increase in public awarenes...

AimTo construct statistical models in order to predict the presence, abundance, and potential virulence of Vibrio vulnificus in surface waters of Chesapeake Bay for implementation in ecological forecasting systems.Methods and ResultsWe evaluated and applied previously published qPCR assays to water samples (n = 1636) collected from Chesapeake Bay f...

Coccolithophores are one of the most abundant eukaryotic phytoplankton in the oceans and are distinguished by their ability to build calcitic platelets (coccoliths). Of the numerous species, Emiliania huxleyi is considered one of the major calcifiers in the pelagic ocean. There is growing concern that increasing levels of CO2 in the atmos- phere an...

The best resolved large-scale biological variable is satellite-measured ocean color whose continuous record spans just over a decade. Using closely correlated physical variables as proxies, chlorophyll concentrations were extended back to 1958 through the canonical correlation method of statistical reconstruction. These were validated through sever...

The Chesapeake Bay Ecological Prediction System (CBEPS) automatically generates daily nowcasts and three-day forecasts of several environmental variables, such as sea-surface temperature and salinity, the concentrations of chlorophyll, nitrate, and dissolved oxygen, and the likelihood of encountering several noxious species, including harmful algal...

Coccolithophores are the primary oceanic phytoplankton responsible for the production of calcium carbonate (CaCO3). These climatically important plankton play a key role in the oceanic carbon cycle as a major contributor of carbon to the open ocean carbonate pump (~50%) and their formation can affect the atmosphere-to-ocean (air-sea) uptake of carb...

This chapter describes on-going regional projects sponsored by the US National Oceanic and Atmospheric Administration and its partners to forecast harmful algal blooms and water-borne pathogens in waters of the US coastal oceans and Great Lakes. Collectively, these provide an introduction to the general problems, the approaches employed, the produc...

An advanced data assimilation system, the local ensemble transform Kalman filter (LETKF), has been interfaced with a Regional Ocean Modeling System (ROMS) implementation on the Chesapeake Bay (ChesROMS) as a first step toward a reanalysis and improved forecast system for the Chesapeake Bay. The LETKF is among the most advanced data assimilation met...

The timing or phenology of the annual cycle of phytoplankton biomass can be monitored to better understand the underpinnings of the marine ecosystem and assess its response to environmental change. Ten-year, global maps of the mean date of bloom onset, peak concentration and termination of bloom duration were constructed by extracting these phenolo...

Salinity is a critical factor in understanding and predicting physical and biogeochemical processes in the coastal ocean where it varies considerably in time and space. In this paper, we introduce a Chesapeake Bay community implementation of the Regional Ocean Modeling System (ChesROMS) and use it to investigate the interannual variability of salin...

Ecological prediction of the impacts of physical, chemical, biological, and human-induced change on ecosystems and their components, encompass a wide range of space and time scales, and subject matter. They vary from predicting the occurrence and/or transport of certain species, such harmful algal blooms, or biogeochemical constituents, such as dis...

Harmful algal blooms are now recognized as a significant threat to the Chesapeake Bay as they can severely compromise the economic viability of important recreational and commercial fisheries in the largest estuary of the United States. This study describes the development of empirical models for the potentially domoic acid-producing Pseudo-nitzsch...

Harmful algal blooms (HABs) are often associated with eutrophication of coastal waters and estuaries. However, identifying quantitative relationships between nutrient input and proliferation of specific algal species is very challenging and complex. The complexity arises from the diversity of sources, forms and fluxes of nutrients both exported int...

Vibrio cholerae, the causative agent of cholera, is a naturally occurring inhabitant of the Chesapeake Bay and serves as a predictor for other clinically important vibrios, including Vibrio parahaemolyticus and Vibrio vulnificus. A system was constructed to predict the likelihood of the presence of V. cholerae in surface waters of the Chesapeake Ba...

The Chesapeake Bay (CB) is the largest estuary in North America and has been listed as impaired under the Clean Water Act since 1998. Deteriorating water conditions are largely due to contaminants carried into the Bay by the many tributaries in the CB watershed. The Earth System Science Interdisciplinary Center of the University of Maryland at Coll...

With access to growing streams of data from monitoring and observing networks, expanding computing power, and increasing model sophistication, ecological forecasting is moving from research realm to proactive management application. While many operational forecasting efforts focus on predicting the physical environment (e.g., precipitation, tides,...

The late stage of the North East Atlantic (NEA) spring bloom was investigated during June 2005 along a transect section from 45 to 66° N between 15 and 20° W in order to characterize the contribution of siliceous and calcareous phytoplankton groups and describe their distribution in relation to environmental factors. We measured several biogeochemi...

ABSTRACT: The North Atlantic spring bloom is one of the largest annual biological events in the ocean, and is characterized by dominance transitions from siliceous (diatoms) to calcareous (coccolithophores) algal groups. To study the effects of future global change on these phytoplankton and the biogeochemical cycles they mediate, a shipboard conti...

Latitudinal gradients in biodiversity are found in both terrestrial and marine environments, but little agreement exists on the mechanisms or ecological causes creating these patterns. Marine biodiversity patterns have been particularly challenging to document, because of the lack of appropriate data sets from ocean basins. We document latitudinal...

Published algorithms were employed to convert SeaWiFS images of normalized water-leaving-radiance to absorption images of CDOM (chromophoric dissolved organic matter). The best performing algorithm was employed to produce decadal time-series of CDOM monthly composites from 1998 through 2007. Deficits in CDOM absorption coefficient for surface water...

1] Climate change is expected to affect the timing and magnitude of numerous environmental conditions, including temperature, wind, and precipitation. Amongst other repercussions, such alterations will engender a response in marine ecosystem productivity manifested by changes in the timing and magnitude of phytoplankton biomass and primary producti...

The causative agent of cholera, Vibrio cholerae, has been shown to be autochthonous to riverine, estuarine, and coastal waters along with its host, the copepod, a significant member of the zooplankton community. Temperature, salinity, rainfall and plankton have proven to be important factors in the ecology of V. cholerae, influencing the transmissi...

We are developing an advanced data assimilation system for the Chesapeake Bay Forecast System, a regional Earth System Prediction model. To accomplish this, the Regional Ocean Modeling System (ROMS) implementation on the Chesapeake Bay (ChesROMS) has been interfaced with the Local Ensemble Transform Kalman Filter (LETKF) to create an efficient data...

Jellyfish blooms are important events controlling plankton dynamics in coastal waters worldwide, yet factors that influence bloom development are not well understood. We used the scyphomedusa Chrysaora quinquecirrha as a model to examine physical factors that control jellyfish populations and to develop an ecological forecasting system. Over 700 in...

Latitudinal species diversity gradients are well documented in terrestrial environments, but observations documenting latitudinal biodiversity gradients in the deep-sea benthos (Rex et al., 1993) were somewhat surprising, given the relatively uniform environmental conditions. The diversity of deep-sea benthic foraminifera from 43 Holocene core tops...

The stable isotopic composition of benthic foraminifera has been widely used to reconstruct deep-ocean circulation, but questions have been raised about the influence of organic carbon flux on the carbon isotopic composition of deep-sea taxa. We show that annual and seasonality of primary productivity in the North Atlantic do not affect δ13C of Pla...

In this paper, we review the state of the art and major challenges in current efforts to incorporate biogeochemical functional groups into models that can be applied on basin-wide and global scales, with an emphasis on models that might ultimately be used to predict how biogeochemical cycles in the ocean will respond to global warming. We define th...

Deep-sea benthic foraminifera from 43 Holocene core tops in the North Atlantic were studied to evaluate the influence of primary productivity and the seasonality of primary productivity on the distributional patterns of species, faunal assemblages, and microhabitat groups. Two faunal assemblages, Epistominella exigua-Alabaminella weddellensis assem...

During the last 30 years, deep-sea benthic foraminifera have been widely used in reconstructing environmental conditions in the deep sea. Initial suggestions of faunal-water mass associations were never substantiated and, instead, organic carbon flux was identified as a primary influence on species and assemblage patterns. Organic carbon flux also...

The Coastal Waters capability on the GOES-R Hyperspectral Environmental Suite will fill a gap in available satellite observations by providing high temporal, spatial and spectral data. An overview of this capability will be presented.

Coastal waters are important ecological systems and vital assets for many nations. Coastal waters are also complex, dynamic environments where a vast array of coupled biological, chemical, geological, and physical processes occurs over multiple time and space scales. The optical environment of coastal waters is particularly complex. There is consid...

During 1998, five episodes of elevated chlorophyll concentration are observed in the Pacific around the Marquesas Islands (140°W, 10°S) in SeaWiFS ocean color observations. Daily positions of geostationary satellite sea surface temperature fronts reveal the influence of the westward propagating tropical instability waves as narrow temperature front...

Spectral backscattering coefficients were determined for 29 species of cultured marine plankton representing 12 classes using a fixed-angle backscattering meter. Using a multi-angle scattering meter, the volume scattering function was measured and a proportionality constant (χ) between β(141°) and b b was determined as 0.82 (±0.01 SE), less than th...

The presence of blooms of the coccolithophore Emiliania huxleyi in the Bering Sea shelf has been studied using satellite imagery in order to ascertain whether its first reported appearance in 1997 is really a new phenomenon for the area. Examination for Emiliania huxleyi blooms in Coastal Zone Color Scanner (CZCS) and Advanced Very High Resolution...

Carbonates are the largest reservoirs of carbon on Earth. From mid-Mesozoic time, the biologically catalyzed precipitation of calcium carbonates by pelagic phytoplankton has been primarily due to the production of calcite by coccolithophorids. In this paper we address the physical and chemical processes that select for coccolithophorid blooms detec...

A new method of locating and viewing ocean surface fronts is demonstrated in animations of daily composites of hourly sea surface temperatures derived from the NOAA Geostationary Operational Environmental Satellites (GOES). The animation of the satellite images allows the human eye to separate the faster-moving residual clouds from slower-moving oc...

The transport of neritic carbonate sediments suspended by strong sustained winds has been observed from land and from low-altitude aircraft. In March 1996, following a sustained gale-force wind event, aerial photographs of offbank sediment transport plumes from the Bahamas Banks were obtained, and these photographs were correlated with Advanced Ver...

Outbreaks of noxious biota, which occur in both aquatic and terrestrial systems, can have considerable negative economic impacts. For example, an increasing frequency of harmful algal blooms worldwide has negatively affected the tourism industry in many regions. Such impacts could be mitigated if the conditions that give rise to these outbreaks wer...

This paper describes the development and implementation of an automated nowcast system to simulate the salinity, temperature and sea nettle (Chrysaora quinquecirrha), a stinging jelly fish, in Chesapeake Bay. The sea nettle periodically infests the waters of the Chesapeake Bay. Predicting its occurrence and alerting the public in advance will reduc...

Shallow carbonate platforms are a significant source of biogenic calcium carbonate (CaCO 3 ) in the marine environment, second in production only to coral reefs. The mechanisms by which platform-derived neritic carbonates are transported to the pelagic water column and deep benthos are significant to the geological history of shallow carbonate plat...

A multispectral classification scheme was developed to detect the cyanobacteria Trichodesmium spp. in satellite data of the sea-viewing wide field-of-view sensor (SeaWiFS). The criteria for this scheme were established from spectral characteristics derived from (1) SeaWiFS imagery of a Trichodesmium bloom located in the South Atlantic Bight and (2)...

The planktonic marine cyanobacterium, Trichodesmium sp., is broadly distributed throughout the oligotrophic marine tropical and sub-tropical oceans. Trichodesmium, which typically occurs in macroscopic bundles or colonies, is noteworthy for its ability to form large surface aggregations and to fix dinitrogen gas. The latter is important because pri...

Monitoring the health of US coastal waters is an important goal of the National Oceanic and Atmospheric Administration (NOAA). Satellite sensors are capable of providing daily synoptic data of large expanses of the US coast. Ocean color sensors, in particular, can be used to monitor the water quality of coastal waters on an operational basis. To ap...

The successful launch of the National Space Development Agency of Japan (NASDA) Ocean Color and Temperature Sensor (OCTS) in August 1996, and the launch of Orbital Science Corporation's (OSC) Sea-viewing Wide-Field-of-view Sensor (SeaWiFS) in August 1997 signaled the beginning of a new era for ocean color research and application. These data may be...

Current and pending oceanographic remote sensing technology allows the conceptualization of a programme designed to investigate ocean island interactions that could induce short-term nearshore fluxes of particulate organic carbon and biogenic calcium carbonate from pelagic island archipelagoes. These events will influence the geochemistry of adjace...

A model was developed to assess the impact of chromophoric dissolved organic matter (CDOM) on phytoplankton production within the euphotic zone. The rate of depth-integrated daily gross primary productivity within the euphotic zone was evaluated as a function of date, latitude, CDONI absorption characteristics, chlorophyll a (chl a) concentration,...

The global distribution pattern of coccolithophrid blooms was mapped in order to ascertain the prevalence of these blooms in the world's oceans and to estimate their worldwide production of CaCO3 and dimethyl sulfide (DMS). Mapping was accomplished by classifying pixels of 5-day global composites of coastal zone color scanner imagery into bloom and...

The temporal and spatial distribution patterns of coccolithophorid blooms in surface waters of the western North Atlantic (40°W–75°W, 40°N–60°N) from 1979 to 1986 were determined by recording the presence of these blooms through visual examination and supervised computer classification of atmospherically-corrected visible Nimbus-7/Coastal Zone Colo...

High concentrations of the coccolithophorid Emiliania huxleyi (Lohm.) Hay et Mohler and/or its detached coccoliths occurred in or near high-reflectance patches observed in contemporaneous visible Advanced Very High Resolution Radiometer (AVHRR) imagery of the Nova S.cotian Shelf and the Grand Bank. This is the first substantiated record of satellit...

Particulate inorganic carbon (calcium carbonate mineral) is produced by pelagic calcifying organisms in the upper layers of the open ocean, it sinks to the deep sea, is partly dissolved and partly stored in the geological archive. This phenomenon, known as the carbonate pump, is an important component of the global carbon cycle and exerts a major i...

In our remote bathymetric studies of shallow coastal waters, it was necessary to measure both incoming irradiance and to place a radiometer a few inches beneath the sea surface to measure upwelling irradiance from the water column while, at the same time, eliminating the measurement of specular reflectance from that surface. An Exotech Model 100BX...

1] Carbonates are the largest reservoirs of carbon on Earth. From mid-Mesozoic time, the biologically catalyzed precipitation of calcium carbonates by pelagic phytoplankton has been primarily due to the production of calcite by coccolithophorids. In this paper we address the physical and chemical processes that select for coccolithophorid blooms de...