Impact of Monsoon-Transported Anthropogenic Aerosols and Sun-Glint on the Satellite-Derived Spectral Remote Sensing Reflectance in the Indian Ocean

Spectral remote sensing reflectance (Rrs(λ), sr−1) is one of the most important products of ocean color satellite missions, where accuracy is essential for retrieval of in-water, bio-optical, and biogeochemical properties. For the Indian Ocean (IO), where Rrs(λ) accuracy has not been well documented, the quality of Rrs(λ) products from Moderate Resolution Imaging Spectroradiometer onboard both Terra (MODIS-Terra) and Aqua (MODIS-Aqua), and Visible Infrared Imaging Radiometer Suite onboard the Suomi National Polar-Orbiting Partnership spacecraft (VIIRS-NPP), is evaluated and inter-compared based on a quality assurance (QA) system, which can objectively grade each individual Rrs(λ) spectrum, with 1 for a perfect spectrum and 0 for an unusable spectrum. Taking the whole year of 2016 as an example, spatiotemporal pattern of Rrs(λ) quality in the Indian Ocean is characterized for the first time, and the underlying factors are elucidated. Specifically, QA analysis of the monthly Rrs(λ) over the IO indicates good quality with the average scores of 0.93 ± 0.02, 0.92 ± 0.02 and 0.92 ± 0.02 for VIIRS-NPP, MODIS-Aqua, and MODIS-Terra, respectively. Low-quality (~0.7) data are mainly found in the Bengal Bay (BB) from January to March, which can be attributed to the imperfect atmospheric correction due to anthropogenic absorptive aerosols transported by the northeasterly winter monsoon. Moreover, low-quality (~0.74) data are also found in the clear oligotrophic gyre zone (OZ) of the south IO in the second half of the year, possibly due to residual sun-glint contributions. These findings highlight the effects of monsoon-transported anthropogenic aerosols, and imperfect sun-glint removal on the Rrs(λ) quality. Further studies are advocated to improve the sun-glint correction in the oligotrophic gyre zone and aerosol correction in the complex ocean–atmosphere environment.

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Northern Indian Ocean Salt Transport (NIOST): Estimation of Fresh and Salt Water Transports in the Indian Ocean using Remote Sensing, Hydrographic Observations and HYCOM Simulations

10.21236/ada598535 ◽

2013 ◽

Author(s):

Subrahmanyam Bulusu

Keyword(s):

Remote Sensing ◽

Indian Ocean ◽

Salt Water ◽

Salt Transport ◽

Northern Indian Ocean ◽

The Indian Ocean

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Monitoring of the 2015 Villarrica Volcano Eruption by Means of DLR’s Experimental TET-1 Satellite

Remote Sensing ◽

10.3390/rs10091379 ◽

2018 ◽

Vol 10 (9) ◽

pp. 1379 ◽

Cited By ~ 5

Author(s):

Simon Plank ◽

Michael Nolde ◽

Rudolf Richter ◽

Christian Fischer ◽

Sandro Martinis ◽

...

Keyword(s):

Infrared Imaging ◽

Thermal Emission ◽

Atmospheric Correction ◽

Landsat 8 ◽

Thermal Anomalies ◽

Villarrica Volcano ◽

Radiant Power ◽

Moderate Resolution Imaging Spectroradiometer ◽

German Aerospace ◽

Active Volcanoes

Villarrica Volcano is one of the most active volcanoes in the South Andes Volcanic Zone. This article presents the results of a monitoring of the time before and after the 3 March 2015 eruption by analyzing nine satellite images acquired by the Technology Experiment Carrier-1 (TET-1), a small experimental German Aerospace Center (DLR) satellite. An atmospheric correction of the TET-1 data is presented, based on the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Global Emissivity Database (GDEM) and Moderate Resolution Imaging Spectroradiometer (MODIS) water vapor data with the shortest temporal baseline to the TET-1 acquisitions. Next, the temperature, area coverage, and radiant power of the detected thermal hotspots were derived at subpixel level and compared with observations derived from MODIS and Visible Infrared Imaging Radiometer Suite (VIIRS) data. Thermal anomalies were detected nine days before the eruption. After the decrease of the radiant power following the 3 March 2015 eruption, a stronger increase of the radiant power was observed on 25 April 2015. In addition, we show that the eruption-related ash coverage of the glacier at Villarrica Volcano could clearly be detected in TET-1 imagery. Landsat-8 imagery was analyzed for comparison. The information extracted from the TET-1 thermal data is thought be used in future to support and complement ground-based observations of active volcanoes.

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A 40-year global dataset of visible channel remote sensing reflectances and coccolithophore bloom occurrence derived from the Advanced Very High Resolution Radiometer catalogue

10.5194/essd-2018-81 ◽

2018 ◽

Author(s):

Benjamin R. Loveday ◽

Timothy Smyth

Keyword(s):

Remote Sensing ◽

High Resolution ◽

Atmospheric Correction ◽

Global Ocean ◽

Climate Data ◽

Ancillary Data ◽

Remote Sensing Reflectance ◽

Data Files ◽

Climate Data Record ◽

Very High

Abstract. A consistently calibrated 40-year length dataset of visible channel remote sensing reflectance has been derived from the Advanced Very High Resolution Radiometer (AVHRR) sensor global time-series. The dataset uses as its source the Pathfinder Atmospheres – Extended (PATMOS-x) v5.3 Climate Data Record (CDR) for top-of-atmosphere (TOA) visible channel reflectances. This paper describes the theoretical basis for the atmospheric correction procedure and its subsequent implementation, including the necessary ancillary data files used and quality flags applied, in order to determine remote sensing reflectance. The resulting dataset is produced at daily, and archived at monthly, resolution, on a 0.1° × 0.1° grid at https://doi.pangaea.de/10.1594/PANGAEA.892175. The primary aim of deriving this dataset is to highlight regions of the global ocean affected by highly reflective blooms of the coccolithophorid Emiliania Huxleyi over the past 40 years.

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Community geometric standards for remote sensing products

10.5194/egusphere-egu21-1327 ◽

2021 ◽

Author(s):

Guoqing (Gary) Lin ◽

Robert Wolfe ◽

Bin Tan ◽

Jaime Nickeson

Keyword(s):

Remote Sensing ◽

Infrared Imaging ◽

European Space Agency ◽

Remote Sensing Data ◽

Performance Standards ◽

Positional Accuracy ◽

Factors Affecting ◽

Remote Sensors ◽

Data Products ◽

Moderate Resolution Imaging Spectroradiometer

<p>We have developed a set of geometric standards for assessing earth observing data products derived from space-borne remote sensors.&#160; We have worked with the European Space Agency (ESA) Earthnet Data Assessment Pilot (EDAP) project to provide a set of guidelines to assess geometric performance in data products from commercial electronic-optical remote sensors aboard satellites such as those from Planet Labs. The guidelines, or the standards, are based on performance from a few NASA procured sensors, such as the Moderate Resolution Imaging Spectroradiometer (MODIS) sensors, the Visible Infrared Imaging Radiometer Suite (VIIRS) sensors and the Advanced Baseline Imager (ABI) sensors. The standards include sensor spatial response, absolute positional accuracy, and band-to-band co-registration. They are tiered in &#8220;basic&#8221;, &#8220;intermediate&#8221; and &#8220;goal&#8221; criteria. These are important geometric factors affecting scientific use of remote sensing data products. We also discuss possible approaches achieving the highest goal in geometric performance standards.</p>

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Influence of anthropogenic aerosols on the total and spectral irradiance at the sea surface during the Indian Ocean Experiment (INDOEX) 1999

Journal of Geophysical Research Atmospheres ◽

10.1029/2000jd000022 ◽

2002 ◽

Vol 107 (D19) ◽

Cited By ~ 9

Author(s):

Jens Meywerk

Keyword(s):

Indian Ocean ◽

Sea Surface ◽

Spectral Irradiance ◽

Anthropogenic Aerosols ◽

The Indian Ocean

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Effect of optically active substances and atmospheric correction schemes on remote-sensing reflectance at a coastal site off Kochi

International Journal of Remote Sensing ◽

10.1080/01431161.2014.926420 ◽

2014 ◽

Vol 35 (14) ◽

pp. 5434-5447 ◽

Cited By ~ 10

Author(s):

P. Minu ◽

Aneesh A. Lotliker ◽

S. S. Shaju ◽

B. SanthoshKumar ◽

P. Muhamed Ashraf ◽

...

Keyword(s):

Remote Sensing ◽

Atmospheric Correction ◽

Optically Active ◽

Coastal Site ◽

Remote Sensing Reflectance ◽

Active Substances ◽

Optically Active Substances

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A 40-year global data set of visible-channel remote-sensing reflectances and coccolithophore bloom occurrence derived from the Advanced Very High Resolution Radiometer catalogue

Earth System Science Data ◽

10.5194/essd-10-2043-2018 ◽

2018 ◽

Vol 10 (4) ◽

pp. 2043-2054 ◽

Cited By ~ 2

Author(s):

Benjamin Roger Loveday ◽

Timothy Smyth

Keyword(s):

Remote Sensing ◽

High Resolution ◽

Atmospheric Correction ◽

Global Ocean ◽

Climate Data ◽

Ancillary Data ◽

Data Set ◽

Remote Sensing Reflectance ◽

Data Files ◽

Very High

Abstract. A consistently calibrated 40-year-long data set of visible-channel remote-sensing reflectance has been derived from the Advanced Very High Resolution Radiometer (AVHRR) sensor global time series. The data set uses as its source the Pathfinder Atmospheres – Extended (PATMOS-x) v5.3 Climate Data Record for top-of-atmosphere (TOA) visible-channel reflectances. This paper describes the theoretical basis for the atmospheric correction procedure and its subsequent implementation, including the necessary ancillary data files used and quality flags applied, in order to determine remote-sensing reflectance. The resulting data set is produced at daily, and archived at monthly, resolution, on a 0.1∘×0.1∘ grid at https://doi.org/10.1594/PANGAEA.892175. The primary aim of deriving this data set is to highlight regions of the global ocean affected by highly reflective blooms of the coccolithophorid Emiliania huxleyi (where lith concentration >2–5×104 mL−1) over the past 40 years.

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