Long-term trends of global maximum atmospheric mixed layer heights derived from radiosonde measurements

The height of the atmospheric mixed layer is a critical parameter controlling the vertical dispersion of pollutants. Here we calculate daily maximum mixed layer height (MMLH) using operational radiosonde and surface meteorological measurements made at 219 carefully selected WMO weather stations and analyze their long-term trends from 1973 to 2018. We found that 74 stations showed significant increases in MMLH, whereas 48 sites showed negative trends. Positive trends are mainly found in Central US, Europe, Africa, East and Southeast Asia and East Australia. Stations over the coastal US, India and West Australia generally exhibit negative trends. The trends can be attributed to changes in vertical temperature gradient ∇ θ v between 950 and 700 hPa and diurnal temperature range (DTR). ∇ θ v in general decreased and caused positive MMLH trends over the majority of the regions. DTR decreases globally, causing negative MMLH trends (corresponding to decreased DTR), and plays a more important role over India and Central Asia

Algorithm · Atmospheric sciences · Geography · Meteorology · Radiosonde · Atmospheric aerosols and clouds · Atmospheric chemistry and aerosols · Climate variability and models · Mathematics · Geology

• Estimates of the Regression Coefficient Based on Kendall's Tau

  Pranab Kumar Sen•Journal of the American…•1968

  Incluir item

• Nonparametric Tests Against Trend

  Henry B Mann•Econometrica•1945

  Incluir item

• Increase of surface solar irradiance across East China related to changes in aerosol properties during the past decade

  Open Access•Jing Li, Yiwei Jiang et al.•Environmental Research Letters•2017

  Incluir item