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The diurnal temperature range (DTR) has generally decreased at global scale according to the IPCC reports and previous publications. Here, we examined the change in DTR within the past four decades and found that DTR decreased in wet areas, but it increased in dry areas. This is because the daily minimum air temperature (Tmin) increased at a slower rate than the daily maximum air temperature (Tmax) in the dry areas, while it increased more rapidly in the wet areas. The changes in cloud cover, water vapour and moisture flux were observed to have contributed to the observed change in DTR. The change in moisture flux largely contributed to this change through the indirect effect on the change in water vapour across the aridity gradient. The significant impact of moisture flux is linked to the differential change in moisture flux between the dry and wet zones. © 2023 The Authors. International Journal of Climatology published by John Wiley & Sons Ltd on behalf of Royal Meteorological Society.

Quantifying the contribution of natural ecosystems on air quality regulation can help to lay the foundation for ecological construction, and to promote the sustainable development of natural ecosystems. To identify the spatio-temporal dynamic changes of natural vegetation regulation on SO2 absorption and the underlying mechanism of these changes in Qinghai Province, an important ecological barrier and the unique natural ecosystems, the Biome-BGC model was improved to simulate the canopy conductance to SO2 and leaf area index (LAI) on the daily scale, and then the SO2 absorption by vegetation was estimated coupling SO2 concentration from satellite data. Our results showed that the annual average SO2 absorption of the natural ecosystems in Qinghai Province was 4.74 x 10(4) tons yr(-1) from 2005 to 2018, accounting for about 40% of the total emissions. Spatially, the ecosystem service of SO2 absorption gradually decreased from southeast to northwest, and varied from 0 in Haixi state to 14.37 kg SO2 ha(-1) yr(-1) in Haibei state. The annual average SO2 absorption in unit area was 0.68 kg SO2 ha(-1) yr(-1), and significantly higher SO2 absorption was observed in summer with 0.45 kg SO2 ha(-1) quarterly. The canopy conductance and LAI controlled by climate variables would be the dominant driving factors for the variation of SO2 absorption for natural ecosystems. The sensitivity analysis showed that SO2 concentration contributed more to the uncertainties of SO2 absorption than the conductance in this study. Our results could provide powerful supports for realistic eco-environmental policy and decision making.

Quantifying the contribution of natural ecosystems on air quality regulation can help to lay the foundation for ecological construction, and to promote the sustainable development of natural ecosystems. To identify the spatio-temporal dynamic changes of natural vegetation regulation on SO2 absorption and the underlying mechanism of these changes in Qinghai Province, an important ecological barrier and the unique natural ecosystems, the Biome-BGC model was improved to simulate the canopy conductance to SO2 and leaf area index (LAI) on the daily scale, and then the SO2 absorption by vegetation was estimated coupling SO2 concentration from satellite data. Our results showed that the annual average SO2 absorption of the natural ecosystems in Qinghai Province was 4.74 x 10(4) tons yr(-1) from 2005 to 2018, accounting for about 40% of the total emissions. Spatially, the ecosystem service of SO2 absorption gradually decreased from southeast to northwest, and varied from 0 in Haixi state to 14.37 kg SO2 ha(-1) yr(-1) in Haibei state. The annual average SO2 absorption in unit area was 0.68 kg SO2 ha(-1) yr(-1), and significantly higher SO2 absorption was observed in summer with 0.45 kg SO2 ha(-1) quarterly. The canopy conductance and LAI controlled by climate variables would be the dominant driving factors for the variation of SO2 absorption for natural ecosystems. The sensitivity analysis showed that SO2 concentration contributed more to the uncertainties of SO2 absorption than the conductance in this study. Our results could provide powerful supports for realistic eco-environmental policy and decision making.

Braille is an effective way for the visually impaired to learn knowledge and obtain information. Braille image recognition aims to automatically detect Braille dots in the whole Braille image. There is no available public datasets for Braille image recognition to push relevant research and evaluate algorithms. This paper constructs a large-scale Double-Sided Braille Image dataset DSBI with detailed Braille recto dots, verso dots and Braille cells annotation. To quickly annotate Braille images, an auxiliary annotation strategy is proposed, which adopts initial automatic detection of Braille dots and modifies annotation results by convenient human-computer interaction method. This labeling strategy can averagely increase label efficiency by six times for recto dots annotation in one Braille image. Braille dots detection is the core and basic step for Braille image recognition. This paper also evaluates some Braille dots detection methods on our dataset DSBI and gives the benchmark performance of recto dots detection. We have released our Braille images dataset on the GitHub website.