1
|
UV Index Forecasting under the Influence of Desert Dust: Evaluation against Surface and Satellite-Retrieved Data. ATMOSPHERE 2020. [DOI: 10.3390/atmos11010096] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Human exposure to healthy doses of UV radiation is required for vitamin D synthesis, but exposure to excessive UV irradiance leads to several harmful impacts ranging from premature wrinkles to dangerous skin cancer. However, for countries located in the global dust belt, accurate estimation of the UV irradiance is challenging due to a strong impact of desert dust on incoming solar radiation. In this work, a UV Index forecasting capability is presented, specifically developed for dust-rich environments, that combines the use of ground-based measurements of broadband irradiances UVA (320–400 nm) and UVB (280–315 nm), NASA OMI Aura satellite-retrieved data and the meteorology-chemistry mesoscale model WRF-Chem. The forecasting ability of the model is evaluated for clear sky days as well as during the influence of dust storms in Doha, Qatar. The contribution of UV radiation to the total incoming global horizontal irradiance (GHI) ranges between 5% and 7% for UVA and 0.1% and 0.22% for UVB. The UVI forecasting performance of the model is quite encouraging with an absolute average error of less than 6% and a correlation coefficient of 0.93. In agreement with observations, the model predicts that the UV Index at local noontime can drop from 10–11 on clear sky days to approximately 6–7 during typical dusty conditions in the Arabian Peninsula—an effect similar to the presence of extensive cloud cover.
Collapse
|
2
|
Griffin D, McLinden CA, Boersma F, Bourassa A, Dammers E, Degenstein D, Eskes H, Fehr L, Fioletov V, Hayden K, Kharol SK, Li SM, Makar P, Martin RV, Mihele C, Mittermeier RL, Krotkov N, Sneep M, Lamsal LN, Ter Linden M, van Geffen J, Veefkind P, Wolde M, Zhao X. High resolution mapping of nitrogen dioxide with TROPOMI: First results and validation over the Canadian oil sands. GEOPHYSICAL RESEARCH LETTERS 2019; 46:1049-1060. [PMID: 33867596 PMCID: PMC8051066 DOI: 10.1029/2018gl081095] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 12/22/2018] [Indexed: 05/20/2023]
Abstract
UNLABELLED TROPOMI, on-board the Sentinel-5 Precursor satellite is a nadir-viewing spectrometer measuring reflected sunlight in the ultraviolet, visible, near-infrared, and shortwave infrared spectral range. From these spectra several important air quality and climate-related atmospheric constituents are retrieved at an unprecedented high spatial resolution, including nitrogen dioxide (NO2). We present the first retrievals of TROPOMI NO2 over the Canadian Oil Sands, contrasting them with observations from the OMI satellite instrument, and demonstrate its ability to resolve individual plumes and highlight its potential for deriving emissions from individual mining facilities. Further, the first TROPOMI NO2 validation is presented, consisting of aircraft and surface in-situ NO2 observations, as well as ground-based remote-sensing measurements between March and May 2018. Our comparisons show that the TROPOMI NO2 vertical column densities are highly correlated with the aircraft and surface in-situ NO2 observations, and the ground-based remote-sensing measurements with a low bias (15-30 %) over the Canadian Oil Sands. PLAIN LANGUAGE SUMMARY Nitrogen dioxide (NO2) is a pollutant that is linked to respiratory health issues and has negative environmental impacts such as soil and water acidification. Near the surface the most significant sources of NO2 are fossil fuel combustion and biomass burning. With a recently launched satellite instrument (TROPOspheric Monitoring Instrument; TROPOMI) NO2 can be measured with an unprecedented combination of accuracy, spatial coverage, and resolution. This work presents the first TROPOMI NO2 measurements near the Canadian Oil Sands and shows that these measurements have an outstanding ability to detect NO2 on a very high horizontal resolution that is unprecedented for satellite NO2 observations. Further, these satellite measurements are in excellent agreement with aircraft and ground-based measurements.
Collapse
Affiliation(s)
- Debora Griffin
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario, Canada
| | - Chris A McLinden
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario, Canada
| | - Folkert Boersma
- Royal Netherlands Meteorological Institute (KNMI), De Bilt, The Netherlands
- Wageningen University, Environmental Sciences Group, Wageningen, The Netherlands
| | - Adam Bourassa
- Institute of Space and Atmospheric Studies, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Enrico Dammers
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario, Canada
| | - Doug Degenstein
- Institute of Space and Atmospheric Studies, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Henk Eskes
- Royal Netherlands Meteorological Institute (KNMI), De Bilt, The Netherlands
| | - Lukas Fehr
- Institute of Space and Atmospheric Studies, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Vitali Fioletov
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario, Canada
| | - Katherine Hayden
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario, Canada
| | - Shailesh K Kharol
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario, Canada
| | - Shao-Meng Li
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario, Canada
| | - Paul Makar
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario, Canada
| | - Randall V Martin
- Dalhousie University, Department of Physics and Atmospheric Science, Halifax, Nova Scotia, Canada
| | - Cristian Mihele
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario, Canada
| | - Richard L Mittermeier
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario, Canada
| | - Nickolay Krotkov
- Laboratory for atmospheric chemistry and dynamics, NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - Maarten Sneep
- Royal Netherlands Meteorological Institute (KNMI), De Bilt, The Netherlands
| | - Lok N Lamsal
- Laboratory for atmospheric chemistry and dynamics, NASA Goddard Space Flight Center, Greenbelt, MD, USA
- Goddard Earth Sciences Technology and Research, Universities Space Research Association, Columbia, MD, USA
| | - Mark Ter Linden
- Royal Netherlands Meteorological Institute (KNMI), De Bilt, The Netherlands
- Science and Technology (S&T), Delft, Netherlands
| | - Jos van Geffen
- Royal Netherlands Meteorological Institute (KNMI), De Bilt, The Netherlands
| | - Pepijn Veefkind
- Royal Netherlands Meteorological Institute (KNMI), De Bilt, The Netherlands
- Delft University of Technology, Delft, The Netherlands
| | - Mengistu Wolde
- National Research Council Canada, Flight Research Laboratory, Ottawa, K1A 0R6, Canada
| | - Xiaoyi Zhao
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario, Canada
| |
Collapse
|
3
|
Cooper MJ, Martin RV, Lyapustin AI, McLinden CA. Assessing snow extent data sets over North America to inform and improve trace gas retrievals from solar backscatter. ATMOSPHERIC MEASUREMENT TECHNIQUES 2018; 11:2983-2994. [PMID: 30450131 PMCID: PMC6235450 DOI: 10.5194/amt-11-2983-2018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Accurate representation of surface reflectivity is essential to tropospheric trace gas retrievals from solar backscatter observations. Surface snow cover presents a significant challenge due to its variability and thus snow-covered scenes are often omitted from retrieval data sets; however, the high reflectance of snow is potentially advantageous for trace gas retrievals. We first examine the implications of surface snow on retrievals from the upcoming TEMPO geostationary instrument for North America. We use a radiative transfer model to examine how an increase in surface reflectivity due to snow cover changes the sensitivity of satellite retrievals to NO2 in the lower troposphere. We find that a substantial fraction (>50%) of the TEMPO field of regard can be snow covered in January, and that the average sensitivity to the tropospheric NO2 column substantially increases (doubles) when the surface is snow covered. We then evaluate seven existing satellite-derived or reanalysis snow extent products against ground station observations over North America to assess their capability of informing surface conditions for TEMPO retrievals. The Interactive Multisensor Snow and Ice Mapping System (IMS) had the best agreement with ground observations (accuracy of 93%, precision of 87%, recall of 83%). Multiangle Implementation of Atmospheric Correction (MAIAC) retrievals of MODIS-observed radiances had high precision (90% for Aqua and Terra), but underestimated the presence of snow (recall of 74% for Aqua, 75% for Terra). MAIAC generally outperforms the standard MODIS products (precision of 51%, recall of 43% for Aqua; precision of 69%, recall of 45% for Terra). The Near-real-time Ice and Snow Extent (NISE) product had good precision (83%) but missed a significant number of snow-covered pixels (recall of 45%). The Canadian Meteorological Centre (CMC) Daily Snow Depth Analysis Data set had strong performance metrics (accuracy of 91%, precision of 79%, recall of 82%). We use the F score, which balances precision and recall, to determine overall product performance (F = 85%, 82(82)%, 81%, 58%, 46(54)% for IMS, MAIAC Aqua(Terra), CMC, NISE, MODIS Aqua(Terra) respectively) for providing snow cover information for TEMPO retrievals from solar backscatter observations. We find that using IMS to identify snow cover and enable inclusion of snow-covered scenes in clear-sky conditions across North America in January can increase both the number of observations by a factor of 2.1 and the average sensitivity to the tropospheric NO2 column by a factor of 2.7.
Collapse
Affiliation(s)
- Matthew J Cooper
- Department of Physics and Atmospheric Science, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Randall V Martin
- Department of Physics and Atmospheric Science, Dalhousie University, Halifax, Nova Scotia, Canada
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA
| | | | - Chris A McLinden
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario, Canada
| |
Collapse
|