New continuous total ozone, UV, VIS and PAR measurements at Marambio, 64° S, Antarctica

Lakkala, Kaisa; Aun, Margit; Sánchez, Ricardo Zanmar; Bernhard, Germar; Asmi, Eija; Meinander, Outi; Nollas, Fernando Martín; Hülsen, Gregor; Karppinen, Tomi; Aaltonen, V.; Arola, Antti; Leeuw, G. de

doi:10.5194/essd-12-947-2020

Cited by 10 publications

(6 citation statements)

References 30 publications

(56 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Over the open ocean, increased UV radiation in spring and summer compared to winter may lead to greater NO₃⁻ production from the photolytically derived oceanic RONO2 source (Fisher et al, 2018). Ground-based studies at various Antarctic sites demonstrate that UV radiation increases throughout spring and is highest in early summer (Lakkala et al, 2020;Li et al, 2020). This, in addition to greater lightning NOx production during spring and summer at the lower southern latitudes (< 40 ⁰S) (Nesbitt et al, 2000) likely explain why higher [NO₃⁻] are observed in spring and summer as compared to winter.…”

Section: Seasonal Variation In Atmospheric No₃⁻ Concentrationsmentioning

confidence: 99%

A seasonal analysis of aerosol NO₃^- sources and NO_x oxidation pathways in the Southern Ocean marine boundary layer

Burger

Joyce

Hastings

et al. 2022

Preprint

View full text Add to dashboard Cite

Abstract. Nitrogen oxides, collectively referred to as NOx (NO + NO2), are an important component of atmospheric chemistry involved in the production and destruction of various oxidants that contribute to the oxidative capacity of the troposphere. The primary sink for NOx is atmospheric nitrate, which has an influence on climate and the biogeochemical cycling of reactive nitrogen. NOx sources and NOx to NO3- formation pathways remain poorly constrained in the remote marine boundary layer of the Southern Ocean (SO), particularly outside of the more frequently sampled summer months. This study presents seasonally resolved measurements of the isotopic composition (δ15N, δ18O and Δ17O) of atmospheric nitrate in coarse mode (> 1μm) aerosols, collected between South Africa and the sea ice edge in summer, winter and spring. Similar latitudinal trends in δ15N-NO3- were observed in summer and spring, suggesting similar NOx sources. Based on δ15N-NO3-, the primary NOx sources were lightning, oceanic alkyl nitrates and snowpack emissions at the low, mid and high latitudes, respectively. Snowpack emissions associated with photolysis were derived from both the Antarctic snowpack as well as from snow on sea ice. A combination of natural NOx sources, likely transported from the lower latitude Atlantic contribute to the background level NO3- observed in winter, with the potential for a stratospheric NOx source evidenced by one sample of Antarctic origin. Low summertime δ18O-NO3- (< ~70 ‰) are consistent with daytime processes involving oxidation by OH dominating nitrate formation, while higher winter and springtime δ18O-NO3- (> ~60 ‰) indicate an increased influence of O3 oxidation (i.e., N2O5, DMS, BrO). Significant linear relationships between δ18O and Δ17O suggest isotopic mixing between H2O(v) and O3 in winter, with the addition of a third endmember (atmospheric O2) becoming relevant in spring. The onset of sunlight in spring, coupled with large sea ice extent, can activate chlorine chemistry with the potential to increase peroxy radical concentrations, contributing to oxidant chemistry in the marine boundary layer.

show abstract

Section: Seasonal Variation In Atmospheric No₃⁻ Concentrationsmentioning

confidence: 99%

A seasonal analysis of aerosol NO₃^- sources and NO_x oxidation pathways in the Southern Ocean marine boundary layer

Burger

Joyce

Hastings

et al. 2022

Preprint

View full text Add to dashboard Cite

show abstract

“…This region has very few measurements of solar UV irradiance and shows extreme UVI throughout the year. In the context of climate change, this region of the world (Southern Hemisphere tropics) could be affected by a decrease in ozone and an increase in UV radiation levels throughout the 21st century (Lamy et al, 2019). UV-Indien measurement sites correspond to various environments (seaside, altitude, urban) and are homogeneously distributed throughout the western Indian Ocean.…”

Section: Ground-based Reference Datamentioning

confidence: 99%

Validation of the TROPOspheric Monitoring Instrument (TROPOMI) surface UV radiation product

et al. 2020

Self Cite

View full text Add to dashboard Cite

Abstract. The TROPOspheric Monitoring Instrument (TROPOMI) onboard the Sentinel-5 Precursor (S5P) satellite was launched on 13 October 2017 to provide the atmospheric composition for atmosphere and climate research. The S5P is a Sun-synchronous polar-orbiting satellite providing global daily coverage. The TROPOMI swath is 2600 km wide, and the ground resolution for most data products is 7.2×3.5 km2 (5.6×3.5 km2 since 6 August 2019) at nadir. The Finnish Meteorological Institute (FMI) is responsible for the development of the TROPOMI UV algorithm and the processing of the TROPOMI surface ultraviolet (UV) radiation product which includes 36 UV parameters in total. Ground-based data from 25 sites located in arctic, subarctic, temperate, equatorial and Antarctic areas were used for validation of the TROPOMI overpass irradiance at 305, 310, 324 and 380 nm, overpass erythemally weighted dose rate/UV index, and erythemally weighted daily dose for the period from 1 January 2018 to 31 August 2019. The validation results showed that for most sites 60 %–80 % of TROPOMI data was within ±20 % of ground-based data for snow-free surface conditions. The median relative differences to ground-based measurements of TROPOMI snow-free surface daily doses were within ±10 % and ±5 % at two-thirds and at half of the sites, respectively. At several sites more than 90 % of cloud-free TROPOMI data was within ±20 % of ground-based measurements. Generally median relative differences between TROPOMI data and ground-based measurements were a little biased towards negative values (i.e. satellite data < ground-based measurement), but at high latitudes where non-homogeneous topography and albedo or snow conditions occurred, the negative bias was exceptionally high: from −30 % to −65 %. Positive biases of 10 %–15 % were also found for mountainous sites due to challenging topography. The TROPOMI surface UV radiation product includes quality flags to detect increased uncertainties in the data due to heterogeneous surface albedo and rough terrain, which can be used to filter the data retrieved under challenging conditions.

show abstract

“…For comparison, level 3 data with 0.25 • resolution from the Ozone Monitoring Instrument (OMI) on board the Aura satellite (Levelt et al, 2018), received through the NASA Giovanni interface (https://giovanni.gsfc.nasa.gov/giovanni/, last access: 14 June 2019), were used. Daily values of the OMI ozone product co-located with the Marambio station (64.125 • S, 56.625 • W for OMI data) were used and the ratio of daily ozone values (OMI / GUV) was calculated.…”

Section: Total Column Ozone Measurementsmentioning

confidence: 99%

Solar UV radiation measurements in Marambio, Antarctica, during years 2017–2019

et al. 2020

Self Cite

View full text Add to dashboard Cite

Abstract. In March 2017, measurements of downward global irradiance of ultraviolet (UV) radiation were started with a multichannel GUV-2511 radiometer in Marambio, Antarctica (64.23∘ S; 56.62∘ W), by the Finnish Meteorological Institute (FMI) in collaboration with the Servicio Meteorológico Nacional (SMN). These measurements were analysed and the results were compared to previous measurements performed at the same site with the radiometer of the Antarctic NILU-UV network during 2000–2008 and to data from five stations across Antarctica. In 2017/2018 the monthly-average erythemal daily doses from October to January were lower than those averaged over 2000–2008 with differences from 2.3 % to 25.5 %. In 2017/2018 the average daily erythemal dose from September to March was 1.88 kJ m−2, while in 2018/2019 it was 23 % larger (2.37 kJ m−2). Also at several other stations in Antarctica the UV radiation levels in 2017/2018 were below average. The maximum UV indices (UVI) in Marambio were 6.2 and 9.5 in 2017/2018 and 2018/2019, respectively, whereas during years 2000–2008 the maximum was 12. Cloud cover, the strength of the polar vortex and the stratospheric ozone depletion are the primary factors that influence the surface UV radiation levels in Marambio. The lower UV irradiance values in 2017/2018 are explained by the high ozone concentrations in November, February and for a large part of October. The role of cloud cover was clearly seen in December, and to a lesser extent in October and November, when cloud cover qualitatively explains changes which could not be ascribed to changes in total ozone column (TOC). In this study, the roles of aerosols and albedo are of minor influence because the variation of these factors in Marambio was small from one year to the other. The largest variations of UV irradiance occur during spring and early summer when noon solar zenith angle (SZA) is low and the stratospheric ozone concentration is at a minimum (the so-called ozone hole). In 2017/2018, coincident low total ozone column and low cloudiness near solar noon did not occur, and no extreme UV indices were measured.

show abstract

New continuous total ozone, UV, VIS and PAR measurements at Marambio, 64° S, Antarctica

Cited by 10 publications

References 30 publications

A seasonal analysis of aerosol NO₃^- sources and NO_x oxidation pathways in the Southern Ocean marine boundary layer

A seasonal analysis of aerosol NO₃^- sources and NO_x oxidation pathways in the Southern Ocean marine boundary layer

Validation of the TROPOspheric Monitoring Instrument (TROPOMI) surface UV radiation product

Solar UV radiation measurements in Marambio, Antarctica, during years 2017–2019

Contact Info

Product

Resources

About

New continuous total ozone, UV, VIS and PAR measurements at Marambio, 64° S, Antarctica

Cited by 10 publications

References 30 publications

A seasonal analysis of aerosol NO3- sources and NOx oxidation pathways in the Southern Ocean marine boundary layer

A seasonal analysis of aerosol NO3- sources and NOx oxidation pathways in the Southern Ocean marine boundary layer

Validation of the TROPOspheric Monitoring Instrument (TROPOMI) surface UV radiation product

Solar UV radiation measurements in Marambio, Antarctica, during years 2017–2019

Contact Info

Product

Resources

About

A seasonal analysis of aerosol NO₃^- sources and NO_x oxidation pathways in the Southern Ocean marine boundary layer

A seasonal analysis of aerosol NO₃^- sources and NO_x oxidation pathways in the Southern Ocean marine boundary layer