Evaluating historic and modern optical techniques for monitoring phytoplankton biomass in the Atlantic Ocean

This is the final version. Available from Frontiers Media via the DOI in this record. Data availability statement: The dataset used for this study is openly available through the British Oceanographic Data Centre (see https://doi.org/10.5285/ f3198e10-faf3-1525-e053-6c86abc0d2f6).Traditional measurements of the Secchi depth (zSD) and Forel-Ule colour were collected alongside modern radiometric measurements of ocean clarity and colour, and in-situ measurements of chlorophyll-a concentration (Chl-a), on four Atlantic Meridional Transect (AMT) cruises. These data were used to evaluate historic and modern optical techniques for monitoring Chl-a, and to evaluate remote-sensing algorithms. Historic and modern optical measurements were broadly consistent with current understanding, with Secchi depth inversely related to Forel-Ule colour and to beam and diffuse attenuation, positively related to the ratio of blue to green remote-sensing reflectance and euphotic depth. The relationship between Secchi depth and Forel-Ule on AMT was found to be in closer agreement to historical relationships when using data of the Forel-Ule colour of infinite depth, rather than the Forel-Ule colour of the water above the Secchi disk at half zSD. Over the range of 0.03-2.95 mg m-3, Chl-a was tightly correlated with these optical variables, with the ratio of blue to green remote-sensing reflectance explaining the highest amount of variance in Chl-a (89%), closely followed by the Secchi depth (85%) and Forel-Ule colour (71-81%, depending on the scale used). Existing algorithms that predict Chl-a from these variables were evaluated, and found to perform well, albeit with some systematic differences. Remote sensing algorithms of Secchi depth were in good agreement with in-situ data over the range of values collected (8.5 - 51.8 m, r2>0.77, unbiased root mean square differences around 4.5 m), but with a slight positive bias (2.0 - 5.4 m). Remote sensing algorithms of Forel-Ule agreed well with Forel-Ule colour data of infinite water (r2>0.68, mean differences <1). We investigated the impact of environmental conditions and found wind speed to impact the estimation of zSD, and propose a path forward to include the effect of wind in current Secchi depth theory. We discuss the benefits and challenges of collecting measurements of the Secchi depth and Forel-Ule colour and propose future directions for research. Our dataset is made publicly available to support the research community working on the topic.UK Research and InnovationNatural Environment Research CouncilEuropean Space AgencyEuropean Space AgencyUK National Centre for Earth Observatio

GLORIA - A globally representative hyperspectral in situ dataset for optical sensing of water quality

The development of algorithms for remote sensing of water quality (RSWQ) requires a large amount of in situ data to account for the bio-geo-optical diversity of inland and coastal waters. The GLObal Reflectance community dataset for Imaging and optical sensing of Aquatic environments (GLORIA) includes 7,572 curated hyperspectral remote sensing reflectance measurements at 1 nm intervals within the 350 to 900 nm wavelength range. In addition, at least one co-located water quality measurement of chlorophyll a, total suspended solids, absorption by dissolved substances, and Secchi depth, is provided. The data were contributed by researchers affiliated with 59 institutions worldwide and come from 450 different water bodies, making GLORIA the de-facto state of knowledge of in situ coastal and inland aquatic optical diversity. Each measurement is documented with comprehensive methodological details, allowing users to evaluate fitness-for-purpose, and providing a reference for practitioners planning similar measurements. We provide open and free access to this dataset with the goal of enabling scientific and technological advancement towards operational regional and global RSWQ monitoring

Ultraviolet-dosis kaarten van Europa ; Een Remote Sensing/GIS toepassing voor onderzoek naar volksgezondheid en milieu

In een proefproject werden remote sensinggegevens van de atmosfeer gebruikt ten behoeve van een studie naar de effecten van veranderingen in de hoeveelheid ultraviolette straling (UV) aan het aardoppervlak en de daaruit resulterende extra risico's voor mens en milieu. Het gepresenteerde model berekent de maandgemiddelde hoeveelheid UV als functie van de ozonkolomdikte, bewolkingsgraad en hoogte boven zeeniveau met hoge ruimtelijke resolutie. De kennis over de verandering in de hoeveelheid UV vormt de basis voor een studie naar veranderingen in risico's van UV blootstelling.In a pilot project remote sensing observations of the atmosphere were used for studying the effects of changing budgets of ultraviolet radiation (UV) on the surface of the earth and the resulting extra risks for humans and the environment. A model is presented to calculate the monthly mean UV budget with high spatial resolution taking thickness of the ozone column, cloudiness and altitude into account. The knowledge on the changes in the UV budget will form the basis of a study to explore the changes in risk related to UV exposure.National User Support Programm

1992 Quadrennial Ozone Symposium. New insights in the ozone production and ozone loss in the free atmosphere

Abstract niet beschikbaarThis report summarises the main results presented during the most recent "Quadrennial Ozone Symposium", held in Charlottesville, Virginia, USA.At the symposium the knowledge on production, loss and transport of ozone in troposphere and stratosphere were highlighted. In the lower troposphere in the Northern Hemisphere ozone is increasing by 1 percent per year. Key questions are how this increase is connected with emissions of NOx, VOC, CH4, and CO, and the role of biomass burning in the tropics. Ozone is decreasing at a rate of 0.5 to 1.5% per year in the stratosphere. The research here is concentrated on the ozone loss in the Arctic regions and heterogeneous reactions on polar stratospheric clouds, background sulphate aerosols and the Pinatubo aerosols.RIV

[Analyse van de mogelijkheden van satellietwaarnemingen van sporegassen in de troposfeer.]

Abstract niet beschikbaarAt present various instruments that will be able to detect trace gases in the stratosphere and troposphere from satellites in space are being developed. We refer, in particular, to the Global Ozone Monitoring Experiment (GOME) of the European Space Agency to be launched on the ERS-2 satellite in 1994/1995 and its successor SCIAMACHY. This report investigates the sensitivity of the GOME spectrometer to detecting changes in the tropospheric column density of ozone (O3), nitrogen dioxide (NO2) sulphur dioxide (SO2) and formaldehyde (HCHO). The results of these GOME sensitivity calculations for measurements of tropospheric O3, NO2, SO2 and HCHO as a function of latitude and season are discussed.TNO-IMW SRON (Stichting Ruimte Onderzoek Nederland

HFCs and the control policy for H(C)FCs and its relation with Dutch policy regarding the emission of greenhouse gases. Scenarios for global and Dutch use of hydrofluorocarbons and their consequences for global warming

Gehydrogeneerde (chloor)fluorkoolwaterstoffen HCFK's en HFK's zijn vervangers voor het gebruik van chloorfluorkoolwaterstoffen (CFK's) en halonen. Omdat HCFK's een kleinere Ozone Depleting Potential (ODP) hebben dan CFK's maar niet gelijk aan nul, terwijl HFK's een ODP van nul hebben, wordt het gebruik van HCFK's op termijn uitgefaseerd. HFK's dragen echter bij aan de versterking van het broeikaseffect: zij hebben een Global Warming Potential (GWP) ongelijk aan nul. In dit rapport worden drie scenario's beschreven, voor Nederland en mondiaal: (1) de 'Londen'-scenario's, waarin HCFK's en HFK's zonder restricties als vervangers voor CFK's en halonen gebruikt worden ; (2) de 'Kopenhagen'-scenario's, waarin behalve CFK's en halonen ook het gebruik van HCFK's op termijn uitgefaseerd wordt, met als gevolg een groter verbruik van HFK's; (3) de 'Additioneel beleid'-scenario's, waarin verondersteld wordt dat alleen stoffen met een ODP van 0 en GWP van 0 of zeer laag gebruikt worden. Er wordt een overzicht gegeven van het toepassingspotentieel van HFK's tot 2000 a 2010 wereldwijd en in Nederland en van de bijdrage aan de emissies van broeikasgassen. Met name wordt aandacht besteed aan de alternatieven, zgn. 0-ODP en laag-GWP of 0-GWP stoffen. Daarnaast worden van HFK's de GWP-waarden en hun onzekerheden besproken. Verder worden de bronnen van emissies beschreven en reductie-mogelijkheden in termen van beschikbare alternatieve stoffen en methoden en reductie bij gebruik ervan. Tenslotte worden conclusies getrokken met betrekking tot mogelijk klimaatbeleid inzake HCFK's en HFK's. Zonder additioneel beleid zal het aandeel van halogeenkoolwaterstoffen in de totale emissie van directe broeikasgassen in Nederland toenemen van ca. 3% in 1990 tot 7 a 11% in 2010 (uitgaande van een GWP van 0 voor CFK's en halonen). Reductie van CFK-gebruik door GWP-0 alternatieven leidt in de meeste scenario's tot stabilisatie op het niveau van 1990. De belangrijkste beperkingen voor additioneel beleid zijn gelegen in beperkte kennis van technisch-economische en veilige beschikbaarheid voor alle toepassingen, gebrek aan informatie over kosten van aanvullend beleid, en de onzekerheid met betrekking tot directe en totale GWP-waarde voor HFK's en alternatieve stoffen. Daarnaast is inzicht in het potentieel van hergebruik belangrijk.Hydrofluorocarbons (HFCs) and hydrochlorofluorocarbons (HCFCs) are important substitutes for chlorofluorocarbons (CFCs) and halons. HCFCs have a lower Ozone Depleting Potential (ODP) than CFCs and halons, and are therefore considered temporary substitutes, while HFCs have zero ODP. In addition to ODP many halocarbons also have a Global Warming Potential (GWP). We developed in this report three different scenarios, globally as well as for the Netherlands: (1) the 'London' scenarios, in which HCFCs and HFCs are used unrestrictedly to replace CFCs and halons ; (2) the 'Copenhagen' scenarios, which consider an additional phase-out of HCFCs, after which the use of HFCs increases ; and (3) the 'Additional Policy' scenario, which assumes the use of compounds, with zero ODP and a relatively small GWP. In this report we describe the potential use of HFCs worldwide and in the Netherlands in 2000/2010 and its contribution to greenhouse gas emissions. Particular attention is given to alternative agents, so-called 0-ODP and low or 0-GWP compounds. In addition the GWP values of HFCs and their uncertainty are discussed. Furthermore, sources of emissions and reduction options by using alternative agents and methods are described. Finally conclusions are presented with respect to options for additional climate policy regarding HCFCs and HFCs. Additional measures will reduce CO2-eq. halocarbon consumption substantially. Without additional policy for HFCs, the share of halocarbons in total CO2 equivalent emissions in the Netherlands will increase from 3 to 7%-11% in 2010 (assuming a zero GWP for CFCs and halons), while substitution by low or zero GWP alternatives leads to stabilization at the 1990 level. Presently the limitations for additional policy are the limited knowledge of the options with regard to technical-economical feasibility, safety aspects, of costs of policy measures and regarding direct and indirect GWPs of HFC compounds and alternative agents. Also, a better insight in the potential for increasing recycling rates is important. A summary of this report has been published in English as paper.DGM/LE-K

HFCs and the control policy for H(C)FCs and its relation with Dutch policy regarding the emission of greenhouse gases. Scenarios for global and Dutch use of hydrofluorocarbons and their consequences for global warming

Hydrofluorocarbons (HFCs) and hydrochlorofluorocarbons (HCFCs) are important substitutes for chlorofluorocarbons (CFCs) and halons. HCFCs have a lower Ozone Depleting Potential (ODP) than CFCs and halons, and are therefore considered temporary substitutes, while HFCs have zero ODP. In addition to ODP many halocarbons also have a Global Warming Potential (GWP). We developed in this report three different scenarios, globally as well as for the Netherlands: (1) the 'London' scenarios, in which HCFCs and HFCs are used unrestrictedly to replace CFCs and halons ; (2) the 'Copenhagen' scenarios, which consider an additional phase-out of HCFCs, after which the use of HFCs increases ; and (3) the 'Additional Policy' scenario, which assumes the use of compounds, with zero ODP and a relatively small GWP. In this report we describe the potential use of HFCs worldwide and in the Netherlands in 2000/2010 and its contribution to greenhouse gas emissions. Particular attention is given to alternative agents, so-called 0-ODP and low or 0-GWP compounds. In addition the GWP values of HFCs and their uncertainty are discussed. Furthermore, sources of emissions and reduction options by using alternative agents and methods are described. Finally conclusions are presented with respect to options for additional climate policy regarding HCFCs and HFCs. Additional measures will reduce CO2-eq. halocarbon consumption substantially. Without additional policy for HFCs, the share of halocarbons in total CO2 equivalent emissions in the Netherlands will increase from 3 to 7%-11% in 2010 (assuming a zero GWP for CFCs and halons), while substitution by low or zero GWP alternatives leads to stabilization at the 1990 level. Presently the limitations for additional policy are the limited knowledge of the options with regard to technical-economical feasibility, safety aspects, of costs of policy measures and regarding direct and indirect GWPs of HFC compounds and alternative agents. Also, a better insight in the potential for increasing recycling rates is important. A summary of this report has been published in English as paper.Gehydrogeneerde (chloor)fluorkoolwaterstoffen HCFK's en HFK's zijn vervangers voor het gebruik van chloorfluorkoolwaterstoffen (CFK's) en halonen. Omdat HCFK's een kleinere Ozone Depleting Potential (ODP) hebben dan CFK's maar niet gelijk aan nul, terwijl HFK's een ODP van nul hebben, wordt het gebruik van HCFK's op termijn uitgefaseerd. HFK's dragen echter bij aan de versterking van het broeikaseffect: zij hebben een Global Warming Potential (GWP) ongelijk aan nul. In dit rapport worden drie scenario's beschreven, voor Nederland en mondiaal: (1) de 'Londen'-scenario's, waarin HCFK's en HFK's zonder restricties als vervangers voor CFK's en halonen gebruikt worden ; (2) de 'Kopenhagen'-scenario's, waarin behalve CFK's en halonen ook het gebruik van HCFK's op termijn uitgefaseerd wordt, met als gevolg een groter verbruik van HFK's; (3) de 'Additioneel beleid'-scenario's, waarin verondersteld wordt dat alleen stoffen met een ODP van 0 en GWP van 0 of zeer laag gebruikt worden. Er wordt een overzicht gegeven van het toepassingspotentieel van HFK's tot 2000 a 2010 wereldwijd en in Nederland en van de bijdrage aan de emissies van broeikasgassen. Met name wordt aandacht besteed aan de alternatieven, zgn. 0-ODP en laag-GWP of 0-GWP stoffen. Daarnaast worden van HFK's de GWP-waarden en hun onzekerheden besproken. Verder worden de bronnen van emissies beschreven en reductie-mogelijkheden in termen van beschikbare alternatieve stoffen en methoden en reductie bij gebruik ervan. Tenslotte worden conclusies getrokken met betrekking tot mogelijk klimaatbeleid inzake HCFK's en HFK's. Zonder additioneel beleid zal het aandeel van halogeenkoolwaterstoffen in de totale emissie van directe broeikasgassen in Nederland toenemen van ca. 3% in 1990 tot 7 a 11% in 2010 (uitgaande van een GWP van 0 voor CFK's en halonen). Reductie van CFK-gebruik door GWP-0 alternatieven leidt in de meeste scenario's tot stabilisatie op het niveau van 1990. De belangrijkste beperkingen voor additioneel beleid zijn gelegen in beperkte kennis van technisch-economische en veilige beschikbaarheid voor alle toepassingen, gebrek aan informatie over kosten van aanvullend beleid, en de onzekerheid met betrekking tot directe en totale GWP-waarde voor HFK's en alternatieve stoffen. Daarnaast is inzicht in het potentieel van hergebruik belangrijk

Aantasting van de ozonlaag en huidkanker: een integrale modelevaluatie

A decrease in stratospheric ozone, probably caused by chlorofluorocarbon (CFC) emissions, has been observed over large parts of the globe. The incidence of skin cancer is expected to increase due to ozone depletion. An integrated source-risk model is developed and applied to evaluate the increased skin cancer incidence related to various CFC emission scenarios. The source-risk model is an independent submodule within the framework of IMAGE, an integrated source-effect-model for climate change and ozone depletion. The model provides estimates for tropospheric concentrations of CFC's, chlorine levels in the stratosphere, ozone depletion, UV irradiance and effects on skin cancer incidence and death rates. The model results show that nu full recovery of the stratospheric chemical balance is expected, even if all countries in the world were to comply to the London Amendments of the Montreal Protocol. Excess death and incidence rates in the Netherlands refering to the additional skin cancer cases caused by ozone depletion are made and compared with preliminary estimated for the USA. The model can be used to evaluate the effects of various new policy options, including the role of CFC alternatives. Furthermore, the model can also be applied for estimating other effects of UV exposure if sufficient information on the exposure-effect relationships becomes available.DGM/SV

[Definition report indices for the atmosphere in environmental assessments.]

Abstract niet beschikbaarenvironmental indices will be an important tool in future environmental assessments (milieubalansen en Milieuverkenningen). This report defines the indices for the atmosphere. It describes the state of definition at the start of the year 1994, and it is the result of the project group in the Laboratory of Air Research (LLO) of RIVM, with support of some experts within and outside of RIVM. This definition needs to be discussed by all the parties involved with environmental assessments, in order to improve the definition and to obtain consensus on it. This report serves as a basis for these discussions. The indices are clustered in human exposure, ecosystem exposure, depletion of stratospheric ozone, climatic change, decreasing self-cleaning capability of the atmosphere, and the damage to the cultural inheritance and the economy. The clusters on human and ecosystem exposure are subdivided into exposure to higher concentrations over a short time (smog), and exposure to concentrations averaged over a time-scale of seasons. Exposure of humans in the indoor environment is also treated separately. The indices are based on several tens of compounds. Concentrations are in general related to internationally accepted "no-effect levels" or "critical levels".DGM/LE RIV

Ozone and Ultraviolet Radiation ; changes, consequences and effects

Dit rapport biedt een overzicht van recent wetenschappelijk onderzoek van het KNMI en RIVM op het gebied van atmosferisch ozon en ultraviolette straling van de zon. Dit onderzoek is er op gericht om inzicht te verwerven in de veranderingen in de hoeveelheid ozon in de atmosfeer, de oorzaken van de veranderingen en de gevolgen daarvan voor de hoeveelheid ultraviolette straling die op het aardoppervlak komt. Sinds 1992 voeren RIVM en KNMI metingen uit in Nederland van de hoeveelheid ozon en UV-straling in de atmosfeer. Het RIVM richt zich daarbij vooral op de milieu- en gezondheidsaspecten van UV en voert scenariostudies uit naar effecten op lange termijn. Het KNMI concentreert zich op de fysisch-atmosferische processen met betrekking tot UV. Daarnaast dragen zij bij aan het ozononderzoek op mondiale schaal. Dit rapport beschrijft wat er zich de afgelopen decennia heeft voorgedaan met de ozonlaag en wat de ontwikkelingen op het gebied van de UV-metingen zijn geweest. Ook wordt uitgebreid aandacht besteed aan de gezondheidseffecten van UV-blootstelling en het effect van beleidsmaatregelen.This report gives an overview of recent scientific research from RIVM and KNMI on atmospheric ozone and solar uv-radiation. This research is aimed at a better understanding of the atmospheric ozone-changes, the processes causing these changes and the resulting UV-radiation at the earth surface. Since 1992 RIVM and KNMI perform atmospheric ozone and UV-measurements. The work of RIVM is especially aimed at the environmental and health-related aspects of UV. They also perform scenario studies of long-term effects of changes. KNMI concentrates more at the physical and atmospheric processes related to UV radiation. Apart from this they contribute to global ozone research. In this report the changes in the ozone layer and the progression in spectral UV-measurements in the previous decades are described. Extensive attention is paid to the health effects of UV-exposure and to the effects of policy measures.RIVM KNMI (Stuurgroep RIVM-KNMI