Fig. 5: The influence of soil moisture on the temperature and circulation in ERA5 reanalysis.
From: Increased impact of heat domes on 2021-like heat extremes in North America under global warming
a The timeseries of maximum temperature (black, unit: °C) and soil moisture (blue, unit: m3 m−3) anomalies (relative to the 1981–2010 average for each calendar day) during 1 May–31 August 2021. b The lead-lag correlation between maximum temperature and soil moisture anomalies in 2021. The negative values of the x-axis indicate that soil moisture leads to temperature. c Histogram (bars) and probability density functions (PDF, solid curve) of simultaneous soil moisture anomalies (unit: m3 m−3) under a similar circulation of 27 June–3 July 2021, and the dashed curves denote the soil moisture anomalies for randomly picked days. The dashed vertical line indicates the soil moisture from 27 June–3 July 2021. d The distribution of the maximum temperature anomalies (detrend, unit: °C) for analogs days generated using detrended soil moisture anomalies from 27 June–3 July 2021 during 1959–2020, 1959–1990, and 1991–2020. The red line indicates the maximum temperature anomalies of the average of 27 June–3 July 2021 from ERA5.
