Ozone, DNA-active UV radiation, and cloud changes for the near-global mean and at high latitudes due to enhanced greenhouse gas concentrations

Abstract

Abstract. This study analyses the variability and trends of ultraviolet-B (UV-B, wavelength 280–320 nm) radiation that can cause DNA damage. The variability and trends caused by climate change due to enhanced greenhouse gas (GHG) concentrations. The analysis is based on DNA-active irradiance, total ozone, total cloud cover, and surface albedo calculations with the European Centre for Medium-Range Weather Forecasts – Hamburg (ECHAM)/Modular Earth Submodel System (MESSy) Atmospheric Chemistry (EMAC) chemistry–climate model (CCM) free-running simulations following the RCP 6.0 climate scenario for the period 1960–2100. The model output is evaluated with DNA-active irradiance ground-based measurements, satellite SBUV (v8.7) total-ozone measurements, and satellite MODerate-resolution Imaging Spectroradiometer (MODIS) Terra cloud cover data. The results show that the model reproduces the observed variability and change in total ozone, DNA-active irradiance, and cloud cover for the period 2000–2018 quite well according to the statistical comparisons. Between 50∘ N–50∘ S, the DNA-damaging UV radiation is expected to decrease until 2050 and to increase thereafter, as was shown previously by Eleftheratos et al. (2020). This change is associated with decreases in the model total cloud cover and negative trends in total ozone after about 2050 due to increasing GHGs. The new study confirms the previous work by adding more stations over low latitudes and mid-latitudes (13 instead of 5 stations). In addition, we include estimates from high-latitude stations with long-term measurements of UV irradiance (three stations in the northern high latitudes and four stations in the southern high latitudes greater than 55∘). In contrast to the predictions for 50∘ N–50∘ S, it is shown that DNA-active irradiance will continue to decrease after the year 2050 over high latitudes because of upward ozone trends. At latitudes poleward of 55∘ N, we estimate that DNA-active irradiance will decrease by 8.2 %±3.8 % from 2050 to 2100. Similarly, at latitudes poleward of 55∘ S, DNA-active irradiance will decrease by 4.8 % ± 2.9 % after 2050. The results for the high latitudes refer to the summer period and not to the seasons when ozone depletion occurs, i.e. in late winter and spring. The contributions of ozone, cloud, and albedo trends to the DNA-active irradiance trends are estimated and discussed.

Unravelling the neglected role of ultraviolet radiation on stomata: A meta‐analysis with implications for modelling ecosystem–climate interactions

“…As well as the variations in the UV‐shielding stratospheric ozone, UV irradiances in the biosphere depend on a range of further factors such as the extent of cloud cover, surface reflectivity and/or aerosols from pollutants, fires and volcanoes (Wild et al, 2021). A neglected process may be the influence of global warming on cloud formation (Eleftheratos et al, 2022; Liu et al, 2023). Satellite data show that cloud cover over the land surface is tending to decrease as the air warms (Liu et al, 2023), and we may expect UV in future decades to increase as a result.…”

“…Thanks to the Montreal Protocol, the destruction of the UV‐shielding stratospheric ozone layer is now largely halted (Barnes et al, 2021). However, UV irradiance levels are still a threat as they are expected to change in tandem with progressing climate change (Barnes et al, 2023; Eleftheratos et al, 2022). Increases in UV irradiance are linked to changes in cloud cover, aerosol concentrations and surface reflectivity, and may reach up to 8% relative to 2017–2020 over the tropics and mid‐latitudes, respectively, by 2100 (Barnes et al, 2023).…”

Network architecture of transcriptomic stress responses in zebrafish embryos

“…In recent years, there has been an increased focus on ectothermic organisms, which are heavily influenced by temperature dynamics (Rebolledo, Sgrò, and Monro 2021; Sokolova 2021). In addition to the increased incidences of abnormally high temperatures during heat waves, organisms must also deal with stress induced by other aspects of the abiotic environment, such as UV radiation (UVR) experienced from sunlight (Dahms and Lee 2010), which is also expected to become more intense due to the effect of greenhouse gases (Eleftheratos et al, 2022). However, aquatic organisms may show more complex responses to combined stressors due to interactive effects (Côté, Darling, and Brown 2016; Piggott, Townsend, and Matthaei 2015).…”

A physically based correction for stray light in Brewer spectrophotometer data analysis

“…Developed in the late 1970s at what is now known as Environment and Climate Change Canada (ECCC), the Brewer spectrophotometer has become an important research and monitoring ground-based instrument to determine, among other quantities, the amount of ozone in the atmosphere and the solar ultraviolet (UV) irradiance reaching the surface (Kerr et al, 1985). As an essential component of V. Savastiouk et al: PHYCS in Brewer data analysis the World Meteorological Organization Global Atmosphere Watch (WMO-GAW) O 3 observing system, the Brewer network, which today consists of more than 200 operating instruments, contributes with its long-term data set to understanding the chemistry and dynamics of the Earth's atmosphere, as well as their variations due to anthropogenic emissions and climate change (Eleftheratos et al, 2022;WMO, 2022;Petkov et al, 2023).…”