Intrusions of Kuroshio and Shelf Waters on Northern Slope of South China Sea in Summer 2015

The northern slope region of the South China Sea(SCS) is a biological hot spot characterized by high primary productivity and biomasses transported by cross-shelf currents, which support the spawning and growth of commercially and ecologically important fish species. To understand the physical and biogeochemical processes that promote the high primary production of this region, we conducted a cruise from June 10 and July 2, 2015. In this study, we used fuzzy cluster analysis and optimum multiparameter analysis methods to analyze the hydrographic data collected during the cruise to determine the compositions of the upper 55-m water masses on the SCS northern slope and thereby elucidate the cross-slope transport of shelf water(SHW) and the intrusions of Kuroshio water(KW). We also analyzed the geostrophic currents derived from acoustic Doppler current profiler measurements and satellite data. The results reveal the surface waters on the northern slope of the SCS to be primarily composed of waters originating from South China Sea water(SCSW), KW, and SHW. The SCSW dominated a majority of the study region at percentages ranging between 60% and 100%. We found a strong cross-slope current with speeds greater than 50 cms^(-1) to have carried SHW into and through the surveyed slope area, and KW to have intruded onto the slope via mesoscale eddies, thereby dominating the southwestern section of the study area.

Paleoenvironments and geochemistry across a continuous Permian-Triassic boundary section at Bukk Mountains,Hungary

The Bálvány North Permian-Triassic boundary sediments were deposited on a carbonate platform in the tropical part of the western Paleo Tethys ocean.The overall elemental geochemistry of the detailed two-metre-thick section across the boundary that we studied shows that the clastic content of the sediments came from dominantly silica-rich continental sources though with some more silica-poor inputs in the uppermost Permian and lowest Triassic limestones as shown by Ni/Al and Nb/Ta ratios.These inputs bracket,but do not coincide with,the main extinctions and associated C,O and S changes.Increased aridity at the Permian-Triassic boundary with increased wind abrasion of suitable Ti-bearing heavy minerals accounts for both the high Ti/Al and Ti/Zr ratios.Various geochemical redox proxies suggest mainly oxic depositional conditions,with episodes of anoxia,but with little systematic variation across the Permian-Triassic extinction boundary.The lack of consistent element geochemical changes across the Permian-Triassic boundary occur not only in adjacent shallower-water marine sections,and in other marine sections along the SW Tethys margin such as the Salt Range sections in Pakistan,but also in deeper shelf and oceanic sections,and in non-marine African and European continental sediments.In the absence of significant changes in physical environments,chemical changes in the atmosphere and oceans,reflected in various isotopic changes,drove the Permian-Triassic extinctions.

Organic carbon content and carbon isotope variations across the Permo-Triassic boundary in the Gartnerkofel-1borehole, Carnic Alps, Austria

The Gartnerkofel borehole is one of the most thoroughly studied and described Permo-Triassic sections in the world. Detailed bulk organic carbon isotope studies show a negative base shift from-24% to-28% in the Latest Permian which latter value persists into the Earliest Triassic after which it decreases slightly to-26%. Two strongly negative peaks of [-38% in the Latest Permian and a lesser peak of-31% in the Early Triassic are too negative to be due to a greater proportion of more negative organic matter and must be due to very negative methane effects. The overall change to more negative values across the Bulla/Tesero boundary fits the relative rise in sea level for this transition based on the facies changes. A positive shift in organic carbon isotope values at the Late Permian Event Horizon may be due to an increase in land-derived organic detritus at this level—a feature shown by allTethyan Permo-Triassic boundary sections though these other sections do not have the same values. Carbonate carbon isotope trends are similar in all sections dropping by2–3 units across the Permo-Triassic boundary. Gartnerkofel carbonate oxygen values are surprisingly, considering the ubiquitous dolomitization, compatible with values elsewhere and indicate reasonable tropical temperatures of 60 °C in the Latest Permian sabkhas to 20–40 °C in the overlying marine transition beds. Increased landderived input at the Late Permian Event Horizon may be due to offshore transport by tsunamis whose deposits have been recognized in India at this level.

EFFICIENCY AND COMFORT THROUGH DEEP ENERGY RETROFITS: BALANCING ENERGY AND MOISTURE MANAGEMENT

Homes that survived to be called“historic”did so because they worked;that is,they delivered a level of performance that met the owner’s expectations and tolerance level without catastrophic damage to the home,pocketbook,or sur­rounding environment.Home performance expectations have changed and now include a desire to use less energy while at the same time realizing a level of comfort that includes air conditioning and constant temperatures in all rooms.In order to meet these performance expectations,old homes often require some“re-engineering.”Increasing insulation will advance energy efficiency goals,reduce costs,and make a home more sustainable but by itself is insufficient,and,often,it can also upset the moisture balance resulting in unexpected mold and sick build­ing syndrome.Improvement in moisture management design is a critically important consideration whenever energy efficiency is increased;however,many projects fail to address moisture adequately.This article will walk through the process of insulating and air sealing a house(two very different activities,sometimes combined,sometimes not),and shed particular light on how different approaches encourage or discourage moisture problems.

A comparison of fecal sampling and direct feeding observations for quantifying the diet of a frugivorous primate

Both observational and indirect evidence are widely used to determine the diets of wild animals.Direct observations are often assumed to provide the most comprehensive reflection of diet,but many wild animals are logistically challenging to observe.Despite the regular use of observa-tional and indirect methods for inferring diet in wild animals,they have rarely been compared in detail for the same study population.Over 12 months this study assessed the congruence of methods in estimating the diet of a montane community of eastern chimpanzees Pan troglodytes schweinfurthii in Nyungwe National Park,Rwanda using observational scan samples and macro-scopic fecal inspection.The assessment of the number of food species consumed each month was comparable between methods,but the estimation of the composition of items in the diet differed significantly.Most notably,the fecal samples significantly underestimated the consumption of flowers,and certain fruit species,which based on direct behavioral observations were seasonally consumed at very high rates.Conversely,direct observations underestimated the consumption of leaves and pith in comparison to results present in the fecal samples.These results suggest that combining methods where possible is most useful for accurate monitoring of dietary trends,particularly for species that experience significant seasonal shifts in their diet.

AntarcticaLC2000：The new Antarctic land cover database for the year 2000

Antarctica plays a key role in global energy balance and sea level change.It has been conventionally viewed as a whole ice body with high albedo in General Circulation Models or Regional Climate Models and the differences of land cover has usually been overlooked.Land cover in Antarctica is one of the most important drivers of changes in the Earth system.Detailed land cover information over the Antarctic region is necessary as spatial resolution improves in land process models.However,there is a lack of complete Antarctic land cover dataset derived from a consistent data source.To fill this data gap,we have produced a database named Antarctic Land Cover Database for the Year 2000(AntarcticaLC2000) using Landsat Enhanced Thematic Mapper Plus(ETM+) data acquired around 2000 and Moderate Resolution Imaging Spectrometer(MODIS) images acquired in the austral summer of 2003/2004 according to the criteria for the 1:100000-scale.Three land cover types were included in this map,separately,ice-free rocks,blue ice,and snow/firn.This classification legend was determined based on a review of the land cover systems in Antarctica(LCCSA) and an analysis of different land surface types and the potential of satellite data.Image classification was conducted through a combined usage of computer-aided and manual interpretation methods.A total of 4067 validation sample units were collected through visual interpretation in a stratified random sampling manner.An overall accuracy of 92.3%and the Kappa coefficient of 0.836 were achieved.Results show that the areas and percentages of ice-free rocks,blue ice,and snow/firn are 73268.81 km2(0.537%),225937.26 km2(1.656%),and 13345460.41 km2(97.807%),respectively.The comparisons with other different data proved a higher accuracy of our product and a more advantageous data quality.These indicate that AntarcticaLC2000,the new land cover dataset for Antarctica entirely derived from satellite data,is a reliable product for a broad spectrum of applications.

Confidence Measure of the Shallow-Water Bathymetry Map Obtained through the Fusion of Lidar and Multiband Image Data

With the advancement of Lidar technology,bottom depth(H)of optically shallow waters(OSW)can be measured accurately with an airborne or space-borne Lidar system(H_(Lidar) hereafter),but this data product consists of a line format,rather than the desired charts or maps,particularly when the Lidar system is on a satellite.Meanwhile,radiometric measurements from multiband imagers can also be used to infer H(H_(imager) hereafter)of OSW with variable accuracy,though a map of bottom depth can be obtained.It is logical and advantageous to use the two data sources from collocated measurements to generate a more accurate bathymetry map of OSW,where usually image-specific empirical algorithms are developed and applied.Here,after an overview of both the empirical and semianalytical algorithms for the estimation of H from multiband imagers,we emphasize that the uncertainty of H_(imager) varies spatially,although it is straightforward to draw regressions between H_(Lidar) and radiometric data for the generation of H_(imager).Further,we present a prototype system to map the confidence of H_(imager) pixel-wise,which has been lacking until today in the practices of passive remote sensing of bathymetry.We advocate the generation of a confidence measure in parallel with H_(imager),which is important and urgent for broad user communities.

Impact of Temperature on Absorption Coefficient of Pure Seawater in the Blue Wavelengths Inferred from Satellite and In Situ Measurements

There has been a long history of interest on how(if)the absorption coefficient of“pure”fresh water(a_(fw)(λ))and“pure”seawater(a_(sw)(λ))changes with temperature(T),yet the impact of T reported in the literature differs significantly in the blue domain.Unlike the previous studies based on laboratory measurements,we took an approach based on~18 years(2002–2020)of MODIS ocean color and temperature measurements in the oligotrophic oceans,along with field measured chlorophyll concentration and phytoplankton absorption coefficient,to examine the relationship between T and the total absorption coefficient(a(λ))at 412 and 443 nm.We found that the values of a(412)and a(443)in the summer are nearly flat(slightly decreasing)for the observed T range of~19–27℃.Since there are no detectable changes of chlorophyll during this period,the results suggest that T has a negligible impact on a_(sw)(412) and a_(sw)(443)in this T range.As a complement,the impact of salinity on a_(fw)(λ) was also evaluated using three independent determinations of a_(sw)(λ) and a_(fw)(λ),where good agreements were found from these observations.

The Use of VGPM to Estimate Oceanic Primary Production:A“Tango”Difficult to Dance

One of the primary goals of launching an ocean color satellite is to obtain over the global ocean synoptic measurements of primary production(PP),a measure of phytoplankton photosynthesis.To reach this ultimate goal,in addition to precise measurements of radiance at the satellite altitude and robust data processing systems,a key requirement is to link primary production with satellitederived products,where a model must be developed and applied.Although many models have been developed in the past decades,the vertically generalized production model(VGPM)developed by Behrenfeld and Falkowski,due to its simplicity and ease of use with satellite products,has been a de facto“standard”for the estimation of PP from ocean color measurements over the past 20+years.Thus,it has significantly influenced the ocean color remote sensing and the biological oceanographic communities.In this article,we discuss the limitations of VGPM(and PP models based on chlorophyll concentration)in estimating primary production.

Progress and Focus of Journal of Remote Sensing in 2021-2022

Introduction of JRS.Remote sensing technology,which emerged in the 1960s,is an increasingly used support for understanding Earth’s past,present,and future and opened a new chapter for humankind to explore Earth[1].

Re-understanding of land surface albedo and related terms in satellite-based retrievals

Land surface albedo is a critical variable in determining surface energy balance,and regulating climate and ecosystem processes through feedback mechanisms.Therefore,climatic modelers and radiative monitoring require accurate estimates of land surface albedo.With the instrument development,algorithm upgrade,spectral-band-adjustment in wavelength center or band width,and the increasing distinct requirement from diversified communities,various albedo terms have been generated in related satellite-based products.The lack of understanding on the divergence of these terminologies can introduce potential considerable errors in the subsequent applications,or an elevated probability to invert the deduced conclusion.We surveyed the basic concepts of reflectance quantities,retrieval strategies,and models developed since the 1970s,and discuss both strength and opportunity for improvements on land surface albedo extraction,and product generation.In addition,we exemplified the difference of albedo terms using the daily MODIS product(MCD43A)to emphasize the potential risk of the ambiguous usage,over typical IGBP land covers in Northern Kazakhstan.Our investigation shows that relative differences among various albedo terms can reach up to 181%and 50%,while 0.266 and 0.118 of absolute variance respectively in the narrow and broad-band surface albedo,which illuminated cautions against the ambiguous understanding of albedo terminologies or erroneous usage of albedo products.

A Portable Algorithm to Retrieve Bottom Depth of Optically Shallow Waters from Top-Of-Atmosphere Measurements

Bottom depth(H)of optically shallow waters can be retrieved from multiband imagery,where remote sensing reflectance(R_(rs))are commonly used as the input.Because of the difficulties of removing the atmospheric effects in coastal areas,quite often,there are no valid R_(rs) from satellites for the retrieval of H.More importantly,the empirical algorithms for H are hardly portable to new measurements.In this study,using data from Landsat-8 and ICESat-2 as examples,we present an approach to retrieve H directly from the top-of-atmosphere(TOA)data.It not only bypasses the requirement to correct the effects of aerosols but also shows promising portability to areas not included in algorithm development.Specifically,we use Rayleigh-corrected TOA reflectance(ρ_(rc))in the 443–2300nm range as input,along with a multilayer perceptron(MLP^(ρ_(rc))_(H)),for the retrieval of H.More than 78,000 matchup points ofρ_(rc)and H(0–25 m)were used to train MLP^(ρ_(rc))_(H),which resulted in a Mean Absolute Percentage Difference(MARD)of 8.8%and a coefficient of determination(R^(2))of 0.96.This MLP^(ρ_(rc))_(H)was further applied to Landsat-8 data of six regions not included in the training phase,generating MARD and R^(2)values of 8.3%and 0.98,respectively.In contrast,a conventional two-band ratio algorithm with R_(rs) as the input generated MARD and R^(2)values of 31.6%and 0.68 and significantly fewer H retrievals due to failures in atmospheric correction.These results indicate a breakthrough of algorithm portability of MLP^(ρ_(rc))_(H)in sensing H of optically shallow waters.

Influence of supraphysiological cortisol manipulation on predator avoidance behaviors and physiological responses to a predation threat in a wild marine teleost fish

The stress axis in teleost fish attempts to maintain internal homeostasis in the face of allostatic loading.However,stress axis induction has been associated with a higher predation rate in fish.To date,the physiological and behavioral factors associated with this outcome are poorly understood.The purpose of the present study was to investigate the impact of experimental cortisol elevation on anti-predator behavior and physiological responses to predator presence.We hypothesized that semi-chronic cortisol elevation would increase susceptibility to predation by increasing stress-induced risk-taking behaviors.To test this hypothesis,schoolmaster snapper were given cocoa butter implants without cortisol(sham)or with cortisol(50 mg/kg body weight)and tethered to cover.Fish were exposed to either a lemon shark or control conditions for 15-min.Space use and activity were recorded throughout and fish were terminally sampled for blood.Cortisol implantation,relative to shams,resulted in higher blood glucose and plasma cortisol concentrations with a lower plasma lactate concentration.Shark exposure,relative to controls,elicited higher blood glucose and lactate concentrations but had no effect on plasma cortisol concentration.No interactions were detected between shark exposure and cortisol treatment for any physiological trait.Behavioral metrics,including shelter use and activity,were unaffected by either cortisol implantation or shark exposure.Physiological responses to cortisol implantation likely resulted from enhanced gluconeogenic activity,whereas alterations under predator exposure may have been the product of catecholamine mobilization.Further work should address context-specific influences of stress in mediating behavioral responses to predation.