Temporal Trends in Satellite-Derived Erythemal UVB and Implications for Ambient Sun Exposure Assessment

Abstract

Ultraviolet radiation (UVR) has been associated with various health outcomes, including skin cancers, vitamin D insufficiency, and multiple sclerosis. Measurement of UVR has been difficult, traditionally relying on subject recall. We investigated trends in satellite-derived UVB from 1978 to 2014 within the continental United States (US) to inform UVR exposure assessment and determine the potential magnitude of misclassification bias created by ignoring these trends. Monthly UVB data remotely sensed from various NASA satellites were used to investigate changes over time in the United States using linear regression with a harmonic function. Linear regression models for local geographic areas were used to make inferences across the entire study area using a global field significance test. Temporal trends were investigated across all years and separately for each satellite type due to documented differences in UVB estimation. UVB increased from 1978 to 2014 in 48% of local tests. The largest UVB increase was found in Western Nevada (0.145 kJ/m2 per five-year increment), a total 30-year increase of 0.87 kJ/m2. This largest change only represented 17% of total ambient exposure for an average January and 2% of an average July in Western Nevada. The observed trends represent cumulative UVB changes of less than a month, which are not relevant when attempting to estimate human exposure. The observation of small trends should be interpreted with caution due to measurement of satellite parameter inputs (ozone and climatological factors) that may impact derived satellite UVR nearly 20% compared to ground level sources. If the observed trends hold, satellite-derived UVB data may reasonably estimate ambient UVB exposures even for outcomes with long latency phases that predate the satellite record.

Vitamin D Nutritional Status and its Related Factors for Chinese Children and Adolescents in 2010–2012

“…The ambient UVB radiation exposure level for each participant was then recorded. The doses were classed into three grades, the annual mean value of UVB, where a value lower than 2900 J/m 2 was defined as low, 2900–3750 J/m 2 was defined as medium, and higher than 3750 J/m 2 was defined as high [ 10 , 11 ]. Body Mass Index (BMI) was calculated according to bodyweight and height.…”

The Ozone Monitoring Instrument: overview of 14 years in space

“…For instance, OMI total ozone column data have been used in several studies to understand the impact of UV exposure on human health (e.g., Beckett et al, 2016;Lucock et al, 2016) similar to the earlier TOMS records (e.g., Boscoe and Schymura, 2006;Chang et al, 2010). A consistent long-term global satellite UV radiation time series is useful for several health-related studies (Langston et al, 2017). For HCHO and NO 2 , the use of the data for health studies has definitely benefited from recent advances in data quality that are the direct result of ongoing OMI retrieval algorithm improvement Bucsela et al, 2013;González Abad, 2015;van Geffen et al, 2015;Marchenko et al, 2015;Krotkov et al, 2017).…”

The Interaction between Viral and Environmental Risk Factors in the Pathogenesis of Multiple Sclerosis

“…It has been proposed that the intensity of ultraviolet B (UVB) radiation, which is essential for vitD synthesis in the skin [90], is lower at northern latitudes [91]. This is because UVB light is readily absorbed by the ozone layer [92]; therefore the increase in the ozone path length at higher latitudes results in decreased UVB light reaching the Earth [93]. This explains low vitD production in all individuals living at higher than 33° latitude [94].…”