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Restoring large, drastically disturbed sites requires active techniques to create stable, self-sustaining native plant communities. We examined the effectiveness of topsoil preparation, seeding, and planting techniques for restoring coastal scrub at a 16.1 ha reclaimed quarry with steep, harsh slopes. Grading within the quarry created a benched slope spanning approximately 230 vertical meters, with a gradient of two horizontal:one vertical (2H:1V). This gentler slope was achieved by cutting the upper portion of the slope and using the cut material to fill the lower portion. Soils on cut slopes (approximately 9.0 ha) and fill slopes (approximately 7.1 ha) were prepared differently, resulting in two distinct substrates. Work crews hydroseeded native shrubs throughout the entire graded slope and installed native shrubs from container plants across half the site. Container plants were irrigated and protected from herbivory and weed competition. We conducted quantitative monitoring of woody vegetation cover for five years. We found that coastal scrub percent vegetative cover established from seed was significantly higher than that from container plantings on fill slopes amended with composted organic matter. Moreover, coastal scrub cover established from seed was significantly higher on amended fill slopes compared to cover from seed or container plants on unamended cut slopes. We conclude that coastal scrub restoration efforts on large, drastically disturbed sites should focus funds and resources on soil preparation, seed application, and site-wide invasive plant control, rather than on container plant installation and maintenance. [ABSTRACT FROM AUTHOR]

A satellite multi-sensor approach is used to analyse the biological response of open ocean regions of the subtropical gyres to changes in physical forcing. Thirteen years (1998–2010) of Sea-viewing Wide Field-of-view Sensor (SeaWiFS) chlorophyll-a (chl-a) data, combined with concurrent satellite records of sea-surface temperature (SST) and sea level height, were analysed to investigate the seasonal and inter-annual variability of chl-a concentration within these immense so-called ocean deserts. The seasonal variability of chl-a within the gyres is driven mostly by the warming/cooling of surface waters. Summer warming promotes shallower mixed layers and lower chl-a due to a reduction of vertical mixing and consequently a decrease in nutrient supply. The opposite happens during the winter cooling period. Therefore, long-term trends in SST have the potential to cause an impact on the inter-annual variability of chl-a. Our analyses show that, during the 13 whole years of SeaWiFS data record, the North Pacific, Indian Ocean and North Atlantic gyres experienced a decrease in chl-a of 9%, 12% and 11%, respectively, with corresponding SST increases of 0.27°C, 0.42°C and 0.32°C, respectively. The South Pacific and South Atlantic gyres also showed warming trends but with weak positive trends in chl-a that are not statistically significant. We hypothesize that the warming of surface waters in these two gyres is counterbalanced by other interacting physical- and biological-driving mechanisms, as indicated in previous studies. [ABSTRACT FROM PUBLISHER]

The subtropical gyres of the world are extensive, coherent regions that occupy about 40% of the surface of the earth. Once thought to be homogeneous and static habitats, there is increasing evidence that mid-latitude gyres exhibit substantial physical and biological variability on a variety of time scales. While biological productivity within these oligotrophic regions may be relatively small, their immense size makes their total contribution significant. Global distributions of dynamic height derived from satellite altimeter data, and chlorophyll concentration derived from satellite ocean-color data, show that the dynamic center of the gyres, the region of maximum dynamic height where the pycnocline is deepest, does not coincide with the region of minimum chlorophyll concentration. The physical and biological processes by which this distribution of ocean properties is maintained, and the spatial and temporal scales of variability associated with these processes, are analyzed using global surface chlorophyll-a concentrations, sea-surface height, sea-surface temperature, surface winds from operational satellite and meteorological sources, and hydrographic data from climatologies and individual surveys. Seasonal and interannual variability in the areal extent of the subtropical gyres are examined using 8 months (November 1996–June 1997) of Ocean-color and Temperature Sensor (OCTS) and 6 years (September 1997–October 03) of Sea-viewing Wide Field-of-View Sensor (SeaWiFS) ocean-color data. The ocean-color data are interpreted in the context of climate variability and measured changes in other ocean properties (i.e. wind forcing, surface currents, Ekman pumping, and vertical mixing). The oligotrophic waters of the North Pacific and North Atlantic gyres are observed to be expanding over this period, while those of the South Pacific, South Atlantic, and South Indian Ocean gyres show much weaker and less consistent tendencies. [Copyright &y& Elsevier]

The Sea-viewing Wide Field-of-view Sensor (SeaWiFS) Project Office was formally initiated at the NASA Goddard Space Flight Center in 1990. Seven years later, the sensor was launched by Orbital Sciences Corporation under a data-buy contract to provide 5 years of science quality data for global ocean biogeochemistry research. To date, the SeaWiFS program has greatly exceeded the mission goals established over a decade ago in terms of data quality, data accessibility and usability, ocean community infrastructure development, cost efficiency, and community service. The SeaWiFS Project Office and its collaborators in the scientific community have made substantial contributions in the areas of satellite calibration, product validation, near-real time data access, field data collection, protocol development, in situ instrumentation technology, operational data system development, and desktop level-0 to level-3 processing software. One important aspect of the SeaWiFS program is the high level of science community cooperation and participation. This article summarizes the key activities and approaches the SeaWiFS Project Office pursued to define, achieve, and maintain the mission objectives. These achievements have enabled the user community to publish a large and growing volume of research such as those contributed to this special volume of Deep-Sea Research. Finally, some examples of major geophysical events (oceanic, atmospheric, and terrestrial) captured by SeaWiFS are presented to demonstrate the versatility of the sensor. [Copyright &y& Elsevier]

Presents a study that analyzed the biological processes in the tropical Pacific Ocean based on ocean-color data collected using the Sea-viewing Wide Field-of-View Sensor. Analysis of biological variability and mesoscale processes; Examination of phytoplankton bloom; Evaluation of penetration irradiance and thermal heating.

Presents an excerpt from the book `In Search of Equality: The Chinese Struggle Against Discrimination in Nineteenth-Century America,' by Charles J. McClain. Rise of anti-Chinese resentment; Calls for anti-Chinese laws by racist elements in the United States; Discriminatory taxes; Legal battles to reinstate full and equal rights to Chinese immigrants.

Reports on algal growth and phytoplankton blooms in the Western Ross Sea through coastal zone color scanners (CZCS). Effect of light and nutrients to phytoplankton production; Effect of seasonal change to phytoplankton production; Effect of low chlorophyll to pigment concentration; Rates of primary production.

An introduction to the special issue of the journal is presented in which the guest editors discuss various reports within the issue on topics related the interactions or marine aerosol, cloud, and climate including chemical composition of marine aerosol, classifying collected marine organic aerosol, and the evaluation of dry deposition of ozone over the North East Atlantic through the use of regional climate model.

The mid-shelf front ( MSF) of the Buenos Aires province continental shelf in the Southwestern Atlantic Ocean plays a central role in the pelagic ecosystem of the region acting as the main spring reproductive area for the northern population of the Argentine anchovy Engraulis anchoita and supporting high concentrations of chlorophyll as well as zooplankton, the main food of anchovy. To investigate the influence of environmental variability on the reproductive success of E. anchoita, we analyzed a 13-yr time series (1997-2009) of environmental data at MSF including chlorophyll dynamics, as well as zooplankton composition and abundance, ichthyoplankton distributions, and recruitment of E. anchoita. Spring chlorophyll concentrations showed high interannual variability and were mainly influenced by changes in water temperature and vertical stratification, which in turn control nutrient supply to the surface. Chlorophyll dynamics (magnitude, timing, and duration of the spring bloom) explained most of the variability observed in E. anchoita recruitment, most likely via fluctuations in the availability of adequate food for the larvae. Our results suggest that satellite ocean color products can be valuable tools for understanding variability in ecosystem dynamics and its effects on the recruitment of fish. [ABSTRACT FROM AUTHOR]

Abstract: Bio-optical measurements of spectral upwelling radiance and surface chlorophyll-a concentration have been conducted during 15 cruises between 1995 and 2004. The bio-optical data were divided into two sub-sets: the Southwestern Atlantic Ocean (SwAO), comprising a variety of biogeochemical provinces, from the oligotrophic waters in the South Atlantic gyre to the coastal waters influenced by La Plata River and Patos Lagoon discharge, and the Southern Ocean (SO) data set, comprising sampling stations south of the mean position of the Polar Front, with most stations being located in the vicinity of the Antarctic Peninsula. We derived regional chlorophyll algorithms for both regions and comparisons were made with the NASA''s OC4v4 (operational algorithm) and OC2v4. For the Southwestern Atlantic region, the NASA OC4v4 algorithm presented a reasonable performance (r 2=0.87, rmse-L=0.475, N=136) as compared to the revised algorithm for SwAO data (r 2=0.89, rmse-L=0.426, N=136). A few stations under strong river plume influence were not considered in the analyses. These were detected by a higher reflectance at 670 nm, at low in situ chlorophyll concentration (<2 mg m−3). These results show that empirical algorithms applied to in-situ radiance data have a limited ability to extract accurate chlorophyll estimates below a 30% uncertainty level. For Southern Ocean stations, a 2-band linear-type model was generated (r 2=0.64, rmse-L=0.347, N=77), which significantly improved the bias (6.4%) as compared to NASA''s OC4v4 algorithm (bias=−21.7%). An evaluation of some published high-latitude algorithms on our data set has shown a better performance by taxon-specific models, even from distant regions. A validation experiment of the normalized spectral water-leaving radiances and chlorophyll-a SeaWiFS products was also conducted using the FURG-SwAO/SO data set, through a match-up exercise. Despite the relatively low number of pairs of radiometric measurements, SeaWiFS estimations compare well with in situ data (0.77<r 2<0.98, N=21), although the satellite estimate show a marked bias (−35.6%) in the blue band nLw (412). Regarding the chlorophyll-a concentration, an overall agreement was observed (r 2=0.77, rmse-L=0.66, N=28), with a mean absolute percentage difference of 66%, which is above the goal generally accepted of 35% for satellite ocean color chlorophyll estimates. For the studied Southern Ocean area (mainly the Bransfield Strait), NASA''s OC4v4 algorithm systematically underestimates chlorophyll above 0.2 mg m−3, as previously demonstrated by other researchers. [Copyright &y& Elsevier]

The effects of penetrative radiation on the upper tropical ocean circulation have been investigated with an ocean general circulation model (OGCM) with attenuation depths derived from remotely sensed ocean color data. The OGCM is a reduced gravity, primitive equation, sigma coordinate model coupled to an advective atmospheric mixed layer model. These simulations use a single exponential profile for radiation attenuation in the water column, which is quite accurate for OGCMs with fairly coarse vertical resolution. The control runs use an attenuation depth of 17 m while the simulations use spatially variable attenuation depths. When a variable depth oceanic mixed layer is explicitly represented with interactive surface heat fluxes, the results can be counterintuitive. In the eastern equatorial Pacific, a tropical ocean region with one of the strongest biological activity, the realistic attenuation depths result in increased loss of radiation to the subsurface, but result in increased sea surface temperatures (SSTs) compared to the control run. Enhanced subsurface heating leads to weaker stratification, deeper mixed layers, reduced surface divergence, and hence less upwelling and entrainment. Thus, some of the systematic deficiencies in the present-day climate models, such as the colder than observed cold tongue in the equatorial Pacific may simply be related to inaccurate representation of the penetrative radiation and can be improved by the formulation presented here. The differences in ecosystems in each of the tropical oceans are clearly manifested in the manner in which biological heat trapping affects the upper ocean. While the tropical Atlantic has many similarities to the Pacific, the Amazon, Congo, and Niger Rivers' discharges dominate the attenuation of radiation. In the Indian Ocean, elevated biological activity and heat trapping are away from the equator in the Arabian Sea and the southern Tropics. For climate models, in view of their sensitivity to... [ABSTRACT FROM AUTHOR]

Studies biospheric primary production during an El Nino-Southern Oscillation (ENSO) transition. Manifestations of temporal changes in the physical environment; Seasonal average and interannual differences in biospheric net primary production; Regional changes resulting from transition from El Nino to La Nina conditions.

The Plankton, Aerosol, Cloud, Ocean Ecosystem (PACE) mission represents the National Aeronautics and Space Administration's (NASA) next investment in satellite ocean color and the study of Earth's ocean–atmosphere system, enabling new insights into oceanographic and atmospheric responses to Earth's changing climate. PACE objectives include extending systematic cloud, aerosol, and ocean biological and biogeochemical data records, making essential ocean color measurements to further understand marine carbon cycles, food-web processes, and ecosystem responses to a changing climate, and improving knowledge of how aerosols influence ocean ecosystems and, conversely, how ocean ecosystems and photochemical processes affect the atmosphere. PACE objectives also encompass management of fisheries, large freshwater bodies, and air and water quality and reducing uncertainties in climate and radiative forcing models of the Earth system. PACE observations will provide information on radiative properties of land surfaces and characterization of the vegetation and soils that dominate their reflectance. The primary PACE instrument is a spectrometer that spans the ultraviolet to shortwave-infrared wavelengths, with a ground sample distance of 1 km at nadir. This payload is complemented by two multiangle polarimeters with spectral ranges that span the visible to near-infrared region. Scheduled for launch in late 2022 to early 2023, the PACE observatory will enable significant advances in the study of Earth's biogeochemistry, carbon cycle, clouds, hydrosols, and aerosols in the ocean–atmosphere–land system. Here, we present an overview of the PACE mission, including its developmental history, science objectives, instrument payload, observatory characteristics, and data products. [ABSTRACT FROM AUTHOR]

Concentrations of the phytoplankton pigment chlorophyll-a (C a) provide indicators of nutrient over-enrichment that has negatively affected Chesapeake Bay, U.S.A. C a time-series from the National Aeronautics and Space Administration (NASA) Sea-viewing Wide Field-of-view Sensor (SeaWiFS) and Moderate Resolution Imaging Spectroradiometer aboard the Aqua spacecraft (MODIS-Aqua) provide observations on temporal and spatial scales that far exceed current field and aircraft sampling strategies. These sensors provide consistent, frequent, and high density data to potentially complement ongoing Bay monitoring activities. We used the in situ Water Quality Monitoring Data set of the Chesapeake Bay Program to evaluate decade-long time-series of SeaWiFS and MODIS-Aqua C a retrievals in the Bay. The accuracy of the retrievals generally degraded with increasing latitude as the optical complexity increases northward. C a derived using empirical (“band ratio”) algorithms overestimated in situ measurements by 10–50 and 40–100% for SeaWiFS and MODIS-Aqua, respectively, but with limited variability. C a derived using spectral-matching algorithms showed less bias for both sensors, but with significant variability and sensitivity to radiometric errors. Regionally-tuned empirical algorithms performed best throughout the Bay, offering a combination of reasonable accuracy and high spatial coverage. The radiometric spectral resolution used as input to the algorithms strongly influenced the quality of C a retrievals from both sensors. These results establish a baseline quantification of algorithm and sensor performance in a variable and stressed ecosystem against which novel approaches might be compared. [Copyright &y& Elsevier]

Abstract: The shelf-break front formed between Argentinean shelf waters and the Malvinas Current (MC) flow shows a conspicuous band of high phytoplankton biomass throughout spring and summer, detected by ocean color sensors. That area is the feeding and spawning ground of several commercial species of fish and squid and is thought to play an important role in CO2 sequestration by the ocean. Phytoplankton blooms in this area have been attributed mainly to coccolithophorids, a group of calcite-producing phytoplankton. Here we present the environmental factors associated with the spring bloom at the Patagonian shelf-break (40°–48°S) in the austral spring 2004. A remarkable bloom of diatoms and dinoflagellates (approximately 1200km long) was observed along the front, where integrated chlorophyll values ranged from 90.3 to 1074mgm−2. It is suggested that supply of macro-nutrients by upwelling and probably iron by both upwelling and shelf transport contribute to maintaining the spring bloom. Strong water column stability along the front allowed the accumulation of algal cells mainly in the top 50m and their maintenance in the euphotic layer. East of the shelf-break front, macronutrient levels were high (surface nitrate=16.6μM, phosphate=0.35μM, silicate=4.0μM), associated with low phytoplankton biomass (<2mgm−3). This was due to mixing and advection associated with the MC flow and to grazing pressure at a transitional site between the MC and the high chlorophyll patch. Primary production rates (determined by the 14C technique) ranged between 1.9 and 7.8gCm−2 d−1. Primary production was highest near 42°S partly because of the elevated phytoplankton biomass, which consumed most of the nitrate and phosphate in surface waters in this region. These high primary production rates are comparable with maximal seasonal productivity at eastern boundary currents. The large bloom extent at the Patagonian shelf-break (approximately 55,000km2 patch of >2mgm−3 chlorophyll), the associated primary production rates and diatom dominance indicate a potentially significant biological control of gases such as O2 and CO2 in surface layers. The main factors favoring the development and maintenance of these blooms are nutrient supply from MC upwelling and water column stability. Other processes such as mixing or grazing play an important role in biomass modulation in the region. [Copyright &y& Elsevier]

Contributing roughly half of the biosphere’s net primary production (NPP), photosynthesis by oceanic phytoplankton is a vital link in the cycling of carbon between living and inorganic stocks. Each day, more than a hundred million tons of carbon in the form of CO2 are fixed into organic material by these ubiquitous, microscopic plants of the upper ocean, and each day a similar amount of organic carbon is transferred into marine ecosystems by sinking and grazing. The distribution of phytoplankton biomass and NPP is defined by the availability of light and nutrients (nitrogen, phosphate, iron). These growth-limiting factors are in turn regulated by physical processes of ocean circulation, mixed-layer dynamics, upwelling, atmospheric dust deposition, and the solar cycle. Satellite measurements of ocean colour provide a means of quantifying ocean productivity on a global scale and linking its variability to environmental factors. Here we describe global ocean NPP changes detected from space over the past decade. The period is dominated by an initial increase in NPP of 1,930 teragrams of carbon a year (Tg C yr-1), followed by a prolonged decrease averaging 190 Tg C yr-1. These trends are driven by changes occurring in the expansive stratified low-latitude oceans and are tightly coupled to coincident climate variability. This link between the physical environment and ocean biology functions through changes in upper-ocean temperature and stratification, which influence the availability of nutrients for phytoplankton growth. The observed reductions in ocean productivity during the recent post-1999 warming period provide insight on how future climate change can alter marine food webs. [ABSTRACT FROM AUTHOR]

Abstract: As part of the Global Carbon Cycle research effort, an agency-wide planning initiative was organized between October 2000 and June 2001 by the NASA Goddard Space Flight Center at the behest of the Associate Administrator for Earth Science. The goal was to define future research and technology development activities needed for implementing a cohesive scientific observation plan. A timeline for development of missions necessary to acquire the selected new measurements was laid out, and included missions for low–medium density terrestrial biomass/coastal ocean, and global ocean carbon. This paper will begin with the scientific justification and measurement requirements for these specific activities, lightly touch on the options for having separate low Earth orbiting missions, and follow-up in more detail with a combined implementation study centered on a hyperspectral imager at geosynchronous altitudes, highlighting both its merits and challenges. [Copyright &y& Elsevier]

In the far southwestern corner of the North Pacific Ocean, the Mindanao Current retroflects and flows northeast into the nascent North Equatorial Countercurrent (NECC). Ocean-color images show that phytoplankton blooms occur both in the nearly closed cyclonic loop of the retroflection, and in the meandering NECC, which were particularly strong during the El Niño event of 1997–98. In the winter of 1997–98, the bloom persisted for about 4 months, and, at its peak, extended for several thousand kilometers along the current stream. The NECC meanders are observed in SeaWiFS and OCTS images at various times throughout the nearly 5 years of data examined, but regionally averaged chlorophyll concentrations during the 1997–98 El Niño were higher than at any time since. The current meanders are sometimes visible in SeaWiFS images during winter, spring and summer, but not in autumn, consistent with the seasonal cycle of formation and decay of the Mindanao Dome (MD). Although the MD has a cyclonic circulation pattern, vertical nutrient flux appears to be maximal in the NECC, which forms its southern boundary, rather than in the MD itself. The appearance of phytoplankton blooms along the stream of the NECC is most plausibly attributed to upwelling associated with current meandering, although El Niño-induced shoaling of the thermocline and seasonal Ekman pumping also may contribute. In addition, transport of nutrient-rich water from the South Pacific by the New Guinea Coastal Undercurrent (NGCUC), which is maximal in boreal winter, creates a gradient of nutrient concentration across the NECC stream with much greater concentrations to the south at a given density (J. Geophys. Res. 103 (1998) 12959). In 1997-98 a confluence of all of these factors occurred. Shoaling of the thermocline and an intensified NECC due to the El Niño event coincided with the seasonal formation of the MD and increased westward transport of nutrient-rich water by the NGCUC to produce the highest chlorophyll concentrations observed in 5 years of ocean-color data. Similar though weaker blooms were observed in the spring of 2003 in association with the very weak 2002–03 El Niño. [Copyright &y& Elsevier]

In this paper, a global validation package for satellite aerosol optical thickness retrieval using the Aerosol Robotic Network (AERONET) observations as ground truth is described. To standardize the validation procedure, the optimum time–space match-up window, the ensemble statistical analysis method, the best selection of AERONET channels, and the numerical scheme used to interpolate/extrapolate these observations to satellite channels have been identified through sensitivity studies. The package is shown to be a unique tool for more objective validation and intercomparison of satellite aerosol retrievals, helping to satisfy an increasingly important requirement of the satellite aerosol remote sensing community. Results of applying the package to the second-generation operational aerosol observational data (AEROBS) from the NOAA-14 Advanced Very High Resolution Radiometer (AVHRR) in 1998 and to the same year aerosol observation data [Clouds and the Earth's Radiant Energy System-Single Scanner Foodprint version 4 (CERES-SSF4)] from the Tropical Rainfall Measuring Mission (TRMM) Visible Infrared Scanner (VIRS) are presented as examples of global validation. The usefulness of the package for identifying improvements to the aerosol optical thickness τ retrieval algorithm is also demonstrated. The principal causes of systematic errors in the current National Oceanic and Atmospheric Administration (NOAA)/National Environmental Satellite, Data, and Information Service (NESDIS) operational aerosol optical thickness retrieval algorithm have been identified and can be reduced significantly, if the correction and adjustment suggested from the global validation are adopted. Random error in the τ retrieval is identified to be a major source of error on deriving the effective Ångström wavelength exponent α and may be associated with regional differences in aerosol particles, which are not accounted for in the current second-generation... [ABSTRACT FROM AUTHOR]

Assesses the system performance of data component of the Sea-viewing Wide Field-of View Sensor (SeaWiFS) Mission to provide useful information for other Earth remote sensing missions. Ocean color data at the Goddard Earth Sciences Distributed Active Archive Center; Data history of SeaWiFS; System architecture history.