A5016416581- Atmospheric Ozone and Climate
- Atmospheric chemistry and aerosols
- Atmospheric and Environmental Gas Dynamics
- Spectroscopy and Laser Applications
- Water Quality Monitoring and Analysis
- Air Quality Monitoring and Forecasting
- Calibration and Measurement Techniques
- Analytical Chemistry and Sensors
- Atmospheric aerosols and clouds
- Geophysics and Gravity Measurements
- Solar and Space Plasma Dynamics
- Radiomics and Machine Learning in Medical Imaging
- Emergency and Acute Care Studies
- Cooperative Studies and Economics
- Distributed and Parallel Computing Systems
- Vehicle emissions and performance
- Ocean Acidification Effects and Responses
- Gas Sensing Nanomaterials and Sensors
- Digital Radiography and Breast Imaging
- Radiology practices and education
- Software Reliability and Analysis Research
- Advanced Chemical Sensor Technologies
- History and Developments in Astronomy
Spectra Energy (Canada)
2011-2014
Spectrum Research (United States)
2013
Environment and Climate Change Canada
2005-2011
Keele University
2005
York University
1997-2005
Dobson and Brewer spectrophotometer filter ozonometer data available from the World Ozone Ultraviolet Data Centre (WOUDC) were compared with satellite total ozone measurements TOMS (onboard Nimbus 7, Meteor 3, Earth Probe satellites), OMI (AURA satellite) GOME (ERS‐2 instruments. Five characteristics of difference calculated for each site instrument type: mean difference, standard deviation daily differences, monthly amplitude seasonal component range annual values. All these five...
It has been more than 20 years since the Brewer reference triad was established by Environment Canada at Toronto. The serves as a for traveling standard instruments that are used to calibrate spectrophotometers around world. members of calibrated on regular basis Mauna Loa, Hawaii. Regular tests made with an internal quartz halogen lamp make it possible track instrument response between calibrations. A new analysis available column ozone data records indicates uncertainty in daily values...
Aerosols from the Sarychev Peak volcano entered Arctic region less than a week after strongest SO 2 eruption on June 15 and 16, 2009 had, by first in July, spread out over entire region. These predominantly stratospheric aerosols were determined to be sub‐micron size inferred composed of sulphates produced condensation gases emitted during eruption. Average (500 nm) Sarychev‐induced optical depths (SOD) Polar Environmental Atmospheric Research Laboratory (PEARL) at Eureka (Nunavut, Canada)...
Abstract. The Optical Spectrograph and Infra-Red Imager System (OSIRIS) the Atmospheric Chemistry Experiment (ACE) have been taking measurements from space since 2001 2003, respectively. This paper presents intercomparisons between ozone NO2 measured by ACE OSIRIS satellite instruments ground-based at Polar Environment Research Laboratory (PEARL), which is located Eureka, Canada (80° N, 86° W) operated Canadian Network for Detection of Change (CANDAC). included in this study are four...
Abstract. From 25 May to 5 June 2015, the 10th regional intercomparison campaign of Regional Brewer Calibration Center – Europe (RBCC-E) was held at El Arenosillo atmospheric sounding station Instituto Nacional de Técnica Aeroespacial (INTA). This jointly conducted by COST Action ES1207 EUBREWNET and Area Instrumentation Atmospheric Research INTA. A total 21 Brewers, 11 single- 10 double-monochromator instruments from countries participated were calibrated for column ozone (TOC) solar UV...
Abstract Column ozone data collected using a Brewer spectrophotometer at Vanscoy, Saskatchewan during the Middle Atmosphere Nitrogen Trend Assessment (MANTRA) balloon campaign (Strong, this issue) were reduced an improved analysis algorithm. The retrieved total values are compared with those from other instruments and good agreement was found. aerosol optical depth has also been calculated same set of results presented. Periods increased coincide periods when plumes smoke nearby forest fires...
Abstract. The availability of long-term records the total ozone content (TOC) represents a valuable source information for studies on assessment short- and atmospheric changes their impact terrestrial ecosystem. In particular, ground-based observations represent tool validating satellite-derived products. To our knowledge, details about software packages processing Brewer spectrophotometer measurements retrieving TOC are seldom specified in using such datasets. sources differences among...
During winter/spring 96/97 ozone levels over the Eureka NDSC observatory (80°N,86°W) were measured using a lidar, sondes, and Brewer spectrophotometer. Column ClO measurements also made an FTIR system. Measurements show that lower stratospheric mixing ratios decreased rapidly between mid‐February late‐March though ratio losses appear to have been less than for 95/96 season. Elevated column amounts of found be present until late March.
Abstract. A new algorithm to retrieve nitrogen dioxide (NO2) column densities using MKIV ("Mark IV") Brewer spectrophotometers is described. The method includes several improvements, such as a more recent spectroscopic data set, the reduction of measurement noise, interference by other atmospheric species and instrumental settings, better determination zenith sky air mass factor. technique was tested during an ad hoc calibration campaign at high-altitude site Izaña (Tenerife, Spain) results...
[1] The Brewer spectrophotometer derives total column ozone from UV measurements using two operational modes: observing either direct sunlight (DS) or zenith sky (ZS) scattered sunlight. While DS are more accurate, ZS necessary for generating long-term time series unbiased by meteorological conditions and the validation of satellite algorithms cloudy scenes. In mode, (X) is obtained slant path (μ) a weighted sum logarithms intensities (F). Prior to this, however, set nine empirical...
Abstract The Middle Atmosphere Nitrogen TRend Assessment (MANTRA) series of high‐altitude balloon flights is being undertaken to investigate changes in the concentrations northern hemisphere mid‐latitude stratospheric ozone, and nitrogen chlorine compounds that play a role ozone chemistry. Four campaigns have been carried out date, all from Vanscoy, Saskatchewan, Canada (52°01'N, 107°02'W, 511.0 m). first MANTRA mission took place August 1998, with flight on 24 1998 Canadian launch large...
Abstract. The data flow involved in a long-term continuous solar spectral UV irradiance monitoring program is investigated and structured to provide an overall view on the multiphase process from acquisition final products. employing Brewer spectrophotometers as measuring instruments maintained by Finnish Meteorological Institute (FMI) ever since 1990s at two sites Finland: Sodankylä (67° N) Jokioinen (61° N). It built upon rigorous operation routines, processing procedures, tools for...
Abstract. Spectral measurements of global UV irradiance recorded by Brewer spectrophotometers can be significantly affected instrument-specific optical and mechanical features. Thus, proper corrections are needed in order to reduce the associated uncertainties within acceptable levels. The present study aims contribute reduction originating from changes internal temperature, which affect performance electronic parts, subsequently response instrument. Until now, various types lamps at...
Abstract. The Brewer ozone spectrophotometer (the Brewer) was designed at Environment and Climate Change Canada (ECCC) in the 1970s to make accurate automated total column measurements. Since 1980s, instrument has become a World Meteorological Organization (WMO) Global Atmosphere Watch (GAW) standard monitoring instrument. Now, more than 230 Brewers have been produced. To assure quality of measurements, calibration chain is maintained, i.e., first, reference instruments are independently...
Abstract. A re-evaluated data set of nitrogen dioxide (NO2) column densities over Rome for the years 1996 to 2017 is here presented. This long-term record obtained from ground-based direct sun measurements with a MkIV Brewer spectrophotometer (serial number #067) and further reprocessed using novel algorithm. Compared original algorithm, new method includes updated NO2 absorption cross sections Rayleigh scattering coefficients, it accounts additional atmospheric compounds instrumental...
Abstract. The Extended-range Atmospheric Emitted Radiance Interferometer (E-AERI) was installed at the Polar Environment Research Laboratory (PEARL) Eureka, Nunavut, Canada in October 2008. Spectra from E-AERI provide information about radiative balance and budgets of trace gases Canadian high Arctic. Measurements are taken every 7 min year-round, including polar night when solar-viewing spectrometers PEARL not operated. This allows measurements to fill gap dataset during four months night....
Ground‐based total ozone (O 3 ) has been measured by Brewer 115 at Hong Kong (Cape D'Aguilar, 22°13′N, 114°15′E, 64 m above mean sea level). Long‐term observations between 1995 and 2005 show that the sensitivity of outdoor spectrophotometers exhibit long‐term drift. Despite undesirable shift, high‐quality can still be achieved so long as spectrophotometer is well maintained calibrated regularly, appropriate corrections applied to data. The recalculated ground‐based also shows good agreement...
Abstract. It is now known that single-monochromator Brewer spectrophotometer ozone and sulfur dioxide measurements suffer from non-linearity at large slant column amounts due to the presence of instrumental stray light caused by scattering within optics instrument. Because gradient in absorption spectrum near-ultraviolet, atmospheric spectra measured instrument possess a very intensity 300 325 nm wavelength region. This results significant sensitivity when there more than 1000 Dobson units...
A new algorithm to determine the nitrogen dioxide column density in atmosphere using MKIV Brewer spectrophotometers is proposed. The updated technique minimizes measurement noise and contribution of several natural instrumental factors that could interfere with measurement. For that, recent spectroscopic data are employed retrieval a set weighting was recalculated taking into account characteristics real Brewer. successfully tested on synthetic spectra simulated radiative transfer code.
Abstract. We describe the steps that are used at Finnish Meteorological Institute (FMI) to process spectral ultraviolet (UV) radiation measurements made with its three Brewer spectrophotometers, located in Sodankylä (67° N) and Jokioinen (61° N). The spectrum is measured many times a day, following pre-programmed schedule. Multiple corrections data near real time (dark current, dead time, stray light, noise spikes, temperature, cosine correction) quality control also performed automatically....
Abstract. Spectral measurements of global UV irradiance recorded by Brewer spectrophotometers can be significantly affected instrument-specific optical and mechanical features, thus proper corrections are needed in order to reduce the associated uncertainties within acceptable levels. The present study aims contribute reduction originating from changes Brewer’s internal temperature, which affect performance electronic parts, subsequently response instrument. Until now, various types lamps at...