Fig. 1

Spatiotemporal distribution of summer MHWs' days in NWP: spatial distribution of the first mode (a), corresponding time series (b), spatial distribution of the second mode (c), and corresponding time series (d)"

Fig. 2

Spatial distribution (left panels) and time series (right panels) of summer MHWs' frequency (a, b), maximum intensity (c, d), duration (e, f), and cumulative intensity (g, h) in the NWP"

Fig. 3

Probability density distribution of SST in the whole region (a), high-latitude region (b), mid-latitude region (c), and low-latitude region (d) of the NWP"

Fig. 4

Anomalous net flux (units: W·m-2, upward being positive) field regressed onto time series of the first mode (a) and the second mode (b) of MHWs' days. The hatched area indicates that the anomalous field passes the 95% confidence test"

Fig. 5

Anomalous shortwave radiation (a), longwave radiation (b), latent heat (c), sensible heat (d) fluxes (units: W·m-2, upward being positive) fields regressed onto time series of the first mode of MHWs' days. Hatching indicates that the anomalous field passes the 95% confidence test"

Fig. 6

Anomalous shortwave radiation (a), longwave radiation (b), latent heat (c), sensible heat (d) fluxes (units: W·m-2, upward being positive) fields regressed onto time series of the second mode of MHWs' days. Hatching indicates that the anomalous field passes the 95% confidence test"

Fig. 7

Distribution of correlation coefficient between atmospheric circulation field and time series of the first mode of MHWs' days: 500-hPa geopotential height (a), 500-hPa air temperature (b), 850-hPa geopotential height (c), and 850-hPa air temperature (d). Vector indicates anomalous wind (units: m·s-1) field regressed onto the time series. Stippling indicates that correlation coefficient passes the 95% confidence test"

Fig. 8

Distribution of correlation coefficient between atmospheric circulation field and linear trend of the first mode of MHWs' days: 500-hPa geopotential height (a), 500-hPa air temperature (b), 850-hPa geopotential height (c), and 850-hPa air temperature (d). Vector indicates anomalous wind (units: m·s-1) field regressed onto the time series. Stippling indicates that correlation coefficient passes the 95% confidence test 图中矢量表示回归到海洋热浪日数第一模态时间序列线性趋势上的风异常场(单位: m·s-1), 打点区表示通过95%显著性检验的区域。审图号为GS(2016)1561"

Fig. 9

Distribution of correlation coefficient between atmospheric circulation field and inter-annual variability of the first mode of MHWs' days: 500-hPa geopotential height (a), 500-hPa air temperature (b), 850-hPa geopotential height (c), and 850-hPa air temperature (d). Vector indicates anomalous wind (units: m·s-1) field regressed onto the time series. Stippling indicates that correlation coefficient passes the 95% confidence test"

Fig. 10

Distribution of correlation coefficient between atmospheric circulation field and time series of the second mode of MHWs' days: 500-hPa geopotential height (a), 500-hPa air temperature (b), 850-hPa geopotential height (c), and 850-hPa air temperature (d). Vector indicates anomalous wind (units: m·s-1) field regressed onto the time series. Stippling indicates that correlation coefficient passes the 95% confidence test"

Fig. 11

Anomalous summer air temperature(units: °C) field in China regressed onto the linear trend of the first mode (a, b), inter-annual variability of the first mode (c, d), and time series of the second mode (e, f) of MHWs' days. Stippling indicates that the anomalous field passes the 95% confidence test"