Irina Petropavlovskikh

A study of regional aerosol radiative properties and effects on ultraviolet‐B radiation

A field experiment was conducted in western North Carolina to investigate the relationship between aerosol optical properties and atmospheric transmission. Two research measurement sites in close horizontal proximity but at different altitudes were established to measure the transmission of UV radiation through a slab of atmosphere. An identical set of radiation sensing instruments, including a broadband UV-B radiometer, a direct Sun pyrheliometer, a shadowband radiometer, and a spectral photometer, was placed at both sites, a mountaintop site (Mount Gibbes 35.78°N, 82.29°W, 2004 m elevation) and a valley site (Black Mountain, North Carolina 35.66°N, 82.38°N, 951 m elevation). Aerosol size distribution sampling equipment was located at the valley site. Broadband solar pseudo-optical depth and aerosol optical depths at 415 nm, 500 nm, and 673 nm were measured for the lowest 1-km layer of the troposphere. The measurements exhibited variations based on an air mass source region as determined by back trajectory analysis. Broadband UV-B transmission through the layer also displayed variations relating to air mass source region. Spectral UV transmission revealed a dependence upon wavelength, with decreased transmission in the UV-B region (300–320 nm) versus UV-A region (320–363.5 nm). UV-B transmission was found to be negatively correlated with aerosol optical depth. Empirical relations were developed to allow prediction of solar noon UV-B transmission if aerosol optical depth at two visible wavelengths (415 and 500 nm) is known. A new method was developed for determining aerosol optical properties from the radiation and aerosol size distribution measurements. The aerosol albedo of single scatter was found to range from 0.75 to 0.93 and the asymmetry factor ranged from 0.63 to 0.76 at 312 nm, which is close to the peak response of human skin to UV radiation.

Performance of the Ozone Mapping and Profiler Suite (OMPS) products

NOAA, through the Joint Polar Satellite System (JPSS) program, in partnership with the National Aeronautical and Space Administration, launched the Suomi National Polar-orbiting Partnership (S-NPP) satellite, a risk reduction and data continuity mission, on 28 October 2011. The JPSS program is executing the S-NPP Calibration and Validation program to ensure that the data products comply with the requirements of the sponsoring agencies. The Ozone Mapping and Profiler Suite (OMPS) consists of two telescopes feeding three detectors measuring solar radiance scattered by the Earths atmosphere directly and solar irradiance by using diffusers. The measurements are used to generate estimates of total column ozone and vertical ozone profiles for use in near-real-time applications and extension of ozone climate data records. The calibration and validation efforts are progressing well, and both Level 1 (Sensor Data Records) and Level 2 (Ozone Environmental Data Records) have advanced to release at Provisional Maturity. This paper provides information on the product performance over the first 22 months of the mission. The products are evaluated through the use of internal consistency analysis techniques and comparisons to other satellite instrument and ground-based products. The initial performance finds total ozone showing negative bias of 2 to 4% with respect to correlative products and ozone profiles often within ±5% in the middle and upper stratosphere of current operational products. Potential improvements in the measurements and algorithms are identified. These will be implemented in coming months to reduce the differences further.

Measurements and products from the Solar Backscatter Ultraviolet (SBUV/2) and Ozone Mapping and Profiler Suite (OMPS) instruments

This paper presents an overview of the state of the National Oceanic and Atmospheric Administration (NOAA) satellite ozone programme including assessments of the current Solar Backscatter Ultraviolet (SBUV/2) and the future Ozone Mapping and Profiler Suite (OMPS) instruments and products. It provides evaluation of the quality of the NOAA Polar-orbiting Operational Satellites (POES) SBUV/2 measurements and the Version 8 algorithm products, both for operational and reprocessed data records. The presentation summarizes work on the instrument calibration and characterization; the algorithm theory and implementation; and the information content, quality and validation of the ozone estimates. This is followed by similar information on the measurements and products expected from the OMPS on the National Polar Operational Environmental Satellite System (NPOESS) and NPOESS Preparatory Project (NPP) beginning in 2011.

Development of a global stratospheric aerosol climatology: Optical properties and applications for UV

A long-term stratospheric aerosol climatology is constructed using SAGE II spectral extinction measurements, worldwide lidar observations, and time series of atmospheric turbidity and transmission data. The results contain important information for assessing stratospheric aerosol effects on ultraviolet (UV) radiation and are intended to provide more accurate stratospheric aerosol corrections for the Umkehr-retrieved ozone profiles. The record, dating from 1953 to 1997, is also useful for climate studies and for estimating errors to other remote sensing methods. A significant part of this study involves examination of the relationships between aerosol size distribution and optical properties as a function of wavelength. These relationships provide empirical means for estimating aerosol extinction at various wavelengths, including UV-B wavelengths, from a single lidar backscatter value or from an extinction value at a different wavelength. A total of 134 size distributions, reported in the literature by several investigators, were used in this analysis. The results suggest the existence of a bounded and predictable domain for aerosol optical properties and indicate distinct differences between volcanic and background aerosol regimes. This paper summarizes the data and methods used in the development of a stratospheric aerosol climatology and illustrates the resulting long-term time series of monthly and zonally averaged stratospheric aerosol optical depth at 0.320 μm. This wavelength was selected because it is close to the midpoint of the Umkehr C-pair wavelengths of 0.311 and 0.332 μm.

Information content of Umkehr and solar backscattered ultraviolet (SBUV) 2 satellite data for ozone trends and solar responses in the stratosphere

Within the past few years, several papers have been published which present updated profile ozone trends from the recently revised ground-based Umkehr record (Miller et al., 1995) and the combined Nimbus 7 solar backscattered ultraviolet (SBUV) and NOAA 11 SBUV 2 satellite data record (Hollandsworth et al., 1995; Miller et al., 1996). Within these papers, however, there has remained an overriding question as to the actual information content of the measurement systems and their ability to detect atmospheric responses. In this paper, we compare the ozone trends and responses to the l 1-year solar cycle (derived from model and/or data specifications of these effects) to results of forward model/retrieval algorithm computations through the algorithms. We consider data at northern midlatitudes (30o-50oN) so that we may compare the satellite results with those of the ground-based systems. Our results indicate that the Umkehr data contain only four independent pieces of information in the vertical and that the SBUV system contains five. In particular, we find that consideration should be restricted to the following regions; Umkehr: the sum of Umkehr layers 1-5, and layers 6, 7, and 8+ (the sum of layers 8 and above), SBUV: the sum of layers 1-5, and layers 6, 7, 8, and 9+ (the sum of layers 9 and above). Additionally, we compare the actual trends and solar coefficients derived in these layers for the periods 1968-1991 and 1979-1991 for the Umkehr and SBUV data. Finally, we include within the latter comparisons the stratospheric aerosol and gas experiment (SAGE) I and II results from Wang et al. (1996) and the computations from the ozonesondes.

Algorithm for the charge-coupled-device scanning actinic flux spectroradiometer ozone retrieval in support of the Aura satellite validation

Stratospheric ozone column data was acquired during four recent aircraft-based validation missions for the Aura satellite flown in years 2004-2006. The data was retrieved by the spectrally-resolved actinic flux measurements of the charge-coupled-device scanning actinic flux spectroradiometer (CAFS) instrument carried on board the NASA WB-57 and DC-8 aircrafts. Each dataset contains information on temporal and spatial variability in the stratospheric ozone column. Analyses of the CAFS datasets provide guidance for assimilation of data from individual satellite orbits into the global maps of stratospheric ozone. Moreover, the 10-second samplings of the CAFS data supply information on spatial variability of stratospheric ozone column across the footprint of a satellite measurement. The CAFS data is available as a function of altitude and geo location of the aircraft. This paper describes the algorithm for the retrieval of an ozone column above the aircraft level, along with validation of the CAFS retrieved ozone product. A discussion of the retrieval uncertainty is provided with emphasis on the algorithms assumptions and instrumental uncertainties. Sensitivity of the ozone retrieval to fundamental atmospheric parameters is discussed in detail, and the range of uncertainties is estimated under a variety of observational conditions. The characteristic model uncertainty of the CAFS partial ozone column retrieval is better than 3 %, whereas the CAFS measurement precision contributes less than 1 % to the retrieval uncertainty.

A Novel Approach to Atmospheric Measurements Using Gliding UASs

Atmospheric aerosols and ozone (O3) have lifetimes of days to weeks and continuously evolve chemically and physically. Frequent and globally spaced vertical profiles of O3, aerosol optical density, particle size distribution, hygroscopic growth, and light absorption coefficients are highly desired in order to understand their controlling processes and subsequent effects on air quality and climate. High costs and logistical restrictions prohibit frequent profiling on a global scale using current technologies. We propose a new approach using state-of-the-art technologies including 3D printing and an unpowered small Unmanned Aircraft System to make the desired measurements at a fraction of the cost of current conventional methods.

NPOESS preparatory project validation plans for the ozone mapping and profiler suite

NOAA, through the Joint Polar Satellite System (JPSS) program, in partnership with National Aeronautical Space Administration (NASA), will launch the NPOESS Preparatory Project (NPP) satellite, a risk reduction and data continuity mission, prior to the first operational JPSS launch. The JPSS program will execute the NPP Calibration and Validation (Cal/Val) program to ensure the data products comply with the requirements of the sponsoring agencies.

Erratum to: The Quadrennial Ozone Symposium 2016

The Quadrennial Ozone Symposium 2016 Sophie GODIN-BEEKMANN*1, Irina PETROPAVLOVSKIKH2, Stefan REIS3,20, Paul NEWMAN4, Wolfgang STEINBRECHT5, Markus REX6, Michelle L. SANTEE7, Richard S. ECKMAN8, Xiangdong ZHENG9, Matthew B. TULLY10, David S. STEVENSON11, Paul YOUNG12, John PYLE13, Mark WEBER14, Johanna TAMMINEN15, Gina MILLS16, Alkiviadis F. BAIS17, Clare HEAVISIDE18, and Christos ZEREFOS191Observatoire de Versailles Saint-Quentin en Yvelines, Université de Versailles Saint-Quentin-en-Yvelines, CNRS, 78280 Guyancourt, France2CIRES, University of Colorado, Boulder, CO 80309, USA3NERC Centre for Ecology & Hydrology, Edinburgh EH26 0QB, UK4Goddard Space Flight Center, NASA, Greenbelt, MD 20771, USA5Hohenpeissenberg Meteorological Observatory, Deutscher Wetterdienst, 82383 Hohenpeissenberg, Germany6Alfred Wegener Institute, 14401 Potsdam, Germany7Jet Propulsion Laboratory, California Institute of Technology, CA 91109, USA8NASA Headquarters, Earth Science Division, Washington, DC, USA9Chinese Academy of Meteorological Sciences, Beijing, 100081, China10Bureau of Meteorology, Melbourne, Victoria 3001, Australia11University of Edinburgh, School of GeoSciences, Edinburgh EH9 3FE, UK12Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK13University of Cambridge, Department of Chemistry, Cambridge CB2 1EW, UK14University of Bremen, Institute of Environmental Physics, 28359 Bremen, Germany15Finnish Meteorological Institute, Earth Observation, FI-00101 Helsinki, Finland16NERC Centre for Ecology and Hydrology, Bangor, Gwynedd LL57 2UW, Wales, UK17Aristotle University of Thessaloniki, Thessaloniki, Greece18Public Health England, Centre for Radiation, Chemical and Environmental Hazards, London, UK19Research Center for Atmospheric Physics & Climatology, Academy of Athens, Athens 10680, Greece20University of Exeter Medical School, Truro TR1 3HD, UK

Suomi National Polar-orbiting Partnership: Verification and early operations for the Ozone Mapping and Profile Suite

A new suite of instruments to estimate atmospheric ozone by measuring scattered solar irradiance began operating in January 2012. The measurements will be used to continue existing records of atmospheric ozone profiles as part of the NOAA Joint Polar Satellite System. This paper presents preliminary evaluations of these new products.