Comparison of ground-based measurements of solar UV radiation at four sites on the Tibetan Plateau

Case series of COVID-19 patients from the Qinghai-Tibetan Plateau Area in China

BACKGROUND

Coronavirus disease 2019 (COVID-19) is a serious infection caused by the new coronavirus severe acute respiratory syndrome coronavirus 2. The disease was first identified in December 2019 and has caused significant morbidity and mortality worldwide.

AIM

To explore the clinical characteristics and treatments for COVID-19 in the Qinghai-Tibetan Plateau Area in China.

METHODS

We retrospectively analyzed the blood cell counts (neutrophils and lymphocytes), blood gas analysis, and thoracic computed tomography changes of patients from Qinghai Province before, during, and after treatment (January 23, 2020 to February 21, 2020). In addition, we summarized and analyzed the information of critical patients. All data were analyzed using SPSS 17.0 (SPSS Inc., Chicago, IL, United States). The quantitative and count variables are represented as the mean ± SD and n (%), respectively.

RESULTS

The main symptoms and signs of patients with COVID-19 were fever, dry cough, cough with phlegm, difficulty breathing, and respiratory distress with a respiration rate ≥ 30 times/min, finger oxygen saturation ≤ 93% in the resting state, and oxygenation index less than 200 but greater than 100 (after altitude correction). Eighteen patients with COVID-19, of whom three were critical, and the others were in a mild condition, were included. The main manifestations included fever, dry cough, and fatigue. Three patients developed difficulty breathing and had a fever. They were eventually cured and discharged. Adjuvant examinations showed one case with reduced white cell count (6%) (< 4 × 109/L), six with reduced count of lymphocytes (33%) (< 0.8 × 109/L), and one with abnormal blood glucose level. All 18 patients were discharged, and no death occurred.

CONCLUSION

Our findings provide critical insight into assessing the clinical diagnosis and treatment for COVID-19 in the Tibetan plateau area.

CDOM Absorption Properties of Natural Water Bodies along Extreme Environmental Gradients

We present absorption properties of colored dissolved organic matter (CDOM) sampled in six different water bodies along extreme altitudinal, latitudinal, and trophic state gradients. Three sites are in Norway: the mesotrophic Lysefjord (LF), Samnangerfjord (SF), and Røst Coastal Water (RCW); two sites are in China: the oligotrophic Lake Namtso (LN) and the eutrophic Bohai Sea (BS); and one site is in Uganda: the eutrophic Lake Victoria (LV). The site locations ranged from equatorial to subarctic regions, and they included water types from oligotrophic to eutrophic and altitudes from 0 m to 4700 m. The mean CDOM absorption coefficients at 440 nm [ a CDOM ( 440 ) ] and 320 nm [ a CDOM ( 320 ) ] varied in the ranges 0.063–0.35 m − 1 and 0.34–2.28 m − 1 , respectively, with highest values in LV, Uganda and the lowest in the high-altitude LN, Tibet. The mean spectral slopes S 280 − 500 and S 350 − 500 were found to vary in the ranges of 0.017–0.032 nm − 1 and 0.013–0.015 nm − 1 , respectively. The highest mean value for S 280 − 500 as well as the lowest mean value for S 350 − 500 were found in LN. Scatter plots of S 280 − 500 versus a CDOM ( 440 ) and a CDOM ( 320 ) values ranges revealed a close connection between RCW, LF, and SF on one side, and BS and LV on the other side. CDOM seems to originate from terrestrial sources in LF, SF, BS, and LV, while RCW is characterized by autochthonous-oceanic CDOM, and LN by autochthonous CDOM. Photobleaching of CDOM is prominent in LN, demonstrated by absorption towards lower wavelengths in the UV spectrum. We conclude that high altitudes, implying high levels of UV radiation and oligotrophic water conditions are most important for making a significant change in CDOM absorption properties.

Environmental effects of ozone depletion and its interactions with climate change: progress report, 2015

The Environmental Effects Assessment Panel (EEAP) is one of three Panels that regularly informs the Parties (countries) to the Montreal Protocol on the effects of ozone depletion and the consequences of climate change interactions with respect to human health, animals, plants, biogeochemistry, air quality, and materials. The Panels provide a detailed assessment report every four years. The most recent 2014 Quadrennial Assessment by the EEAP was published as a special issue of seven papers in 2015 (Photochem. Photobiol. Sci., 2015, 14, 1-184). The next Quadrennial Assessment will be published in 2018/2019. In the interim, the EEAP generally produces an annual update or progress report of the relevant scientific findings. The present progress report for 2015 assesses some of the highlights and new insights with regard to the interactive nature of the effects of UV radiation, atmospheric processes, and climate change.

Validation of ozone monitoring instrument ultraviolet index against ground-based UV index in Kampala, Uganda

The Ozone Monitoring Instrument (OMI) overpass solar ultraviolet (UV) indices have been validated against the ground-based UV indices derived from Norwegian Institute for Air Research UV measurements in Kampala (0.31° N, 32.58° E, 1200 m), Uganda for the period between 2005 and 2014. An excessive use of old cars, which would imply a high loading of absorbing aerosols, could cause the OMI retrieval algorithm to overestimate the surface UV irradiances. The UV index values were found to follow a seasonal pattern with maximum values in March and October. Under all-sky conditions, the OMI retrieval algorithm was found to overestimate the UV index values with a mean bias of about 28%. When only days with radiation modification factor greater than or equal to 65%, 70%, 75%, and 80% were considered, the mean bias between ground-based and OMI overpass UV index values was reduced to 8%, 5%, 3%, and 1%, respectively. The overestimation of the UV index by the OMI retrieval algorithm was found to be mainly due to clouds and aerosols.

Long-term comparisons of UV index values derived from a NILU-UV instrument, NWS, and OMI in the New York area

A comparison is presented of UV index (UVI) values obtained under different cloud conditions from a Norwegian Institute for Air Research UV (NILU-UV) instrument, the ozone monitoring instrument (OMI) onboard the Aura satellite, and the National Weather Service (NWS) model for the time period of 2010-2014. The NILU-UV irradiance meter is a ground-based, multi-channel, moderate bandwidth filter instrument. UVI values derived from measurements by a NILU-UV instrument deployed in the New York area (40.74°N, -74.03°E) to monitor the erythemal UV radiation from 2010 to present is compared to UVI values derived from OMI measurements and predicted by the NWS model. OMI overestimated the UVI values by 13.06% for all cloud conditions compared with the UVI values derived from measurements by the NILU-UV instrument. The heavier the cloud cover, the higher the overestimation. The mean relative difference between the UVI derived from the NWS model and from NILU-UV measurements was 11.54%. The UVI prediction by NWS was also overestimated under cloudy conditions. Under overcast conditions the NWS predictions of UVI values differ significantly from those derived from NILU-UV measurements, yielding a correlation of only 0.8025 and a mean relative difference of 28.25%.

Ozone depletion and climate change: impacts on UV radiation

Percentage changes in the UV Index (UVI) for 2090 relative to 2015 due to changes in ozone (left) and aerosols (right) only. Large decreases are projected over Antarctica due to stratospheric ozone recovery. Increases are projected for parts of Asia due to decreases in aerosols, partly reversing the possible large reductions in UVI after the 1950s.

Comparisons of three NILU-UV instruments deployed at the same site in the New York area

The Norwegian Institute for Air Research ultraviolet (NILU-UV) irradiance meter is a ground-based, multichannel, moderate bandwidth filter instrument that measures irradiances at ultraviolet (UV) and visible wavelengths with five channels in the UV (302, 312, 320, 340, and 380 nm) and one channel in the visible (400-700 nm) part of the spectrum. Minute-by-minute irradiances recorded in these channels are used to infer the total ozone column (TOC) amount, and a radiation modification factor (RMF) designed to have a value close to 100 under cloud-free conditions. The performance of three NILU-UV instruments deployed side-by-side in the New York area (40.74°N, -74.03°E) is assessed, and derived TOC values are compared with those derived from the ozone monitoring instrument (OMI) deployed on NASA's AURA satellite. Based on about three years of data, it was found that the three instruments yielded similar TOC values that were in close agreement with those derived from the OMI. The relative difference in TOC values derived from the three NILU-UV instruments was generally less than 2.5%. Cloud cover affects the accuracy of the inferred TOC, but reliable values can be obtained in the presence of clouds, although the accuracy deteriorates under heavy overcast conditions with RMF values smaller than 65 (low cloud transmittance).