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The current version of HadISDH.extremes is 1.0.0.2021f. For previous versions please contact the dataset maintainers.
These data are available under a free and unrestricted Open Government Licence UK.
NetCDF gridded files contain fields on 5° by 5° resolution from 177.5° W/87.5° N to 177.5° E/87.5° S based on the 19912020 climatology period.
Missing data are represented by 1e30.
Extremes Indices Descriptions  

Short Name  Field Name  Unit  Long Name  Description 
TwX  tw_max  ° C  maximum wet bulb temperature  Gridbox mean of station month maxima of daily maxima Tw 
TwXX  tw_max_max  ° C  maximum maximum wet bulb temperature  Gridbox maximum of station month maxima of daily maxima Tw 
TwX90p  tw_max_90p  % days per month  90th percentile maximum wet bulb temperature exceedance  Gridbox mean of station percentages of days where the daily maximum Tw exceeds the climatological 90th percentile of daily maxima for the month 
TwM90p  tw_mean_90p  % days per month  90th percentile mean wet bulb temperature exceedance  Gridbox mean of station percentages of days where the daily mean Tw exceeds the climatological 90th percentile of daily means for the month 
TwM10p  tw_mean_10p  % days per month  10th percentile mean wet bulb temperature exceedance  Gridbox mean of station percentages of days where the daily mean Tw is lower than the climatological 10th percentile of daily means for the month 
TwN10p  tw_min_10p  % days per month  10th percentile minimum wet bulb temperature exceedance  Gridbox mean of station percentages of days where the daily minimum Tw is lower than the climatological 10th percentile of daily minima for the month 
TwN  tw_min  ° C  Minimum daily minima wet bulb temperature  Gridbox mean of station month minima of daily minima Tw 
TwX25  tw_max_ex25  % days per month  25 ° C maximum wet bulb temperature exceedance  Gridbox mean of station percentages of days where the daily maximum Tw is equal to or exceeds 25 ° C 
TwX27  tw_max_ex27  % days per month  27 ° C maximum wet bulb temperature exceedance  Gridbox mean of station percentages of days where the daily maximum Tw is equal to or exceeds 27 ° C 
TwX29  tw_max_ex29  % days per month  29 ° C maximum wet bulb temperature exceedance  Gridbox mean of station percentages of days where the daily maximum Tw is equal to or exceeds 29 ° C 
TwX31  tw_max_ex31  % days per month  31 ° C maximum wet bulb temperature exceedance  Gridbox mean of station percentages of days where the daily maximum Tw is equal to or exceeds 31 ° C 
TwX33  tw_max_ex33  % days per month  33 ° C maximum wet bulb temperature exceedance  Gridbox mean of station percentages of days where the daily maximum Tw is equal to or exceeds 33 ° C 
TwX35  tw_max_ex35  % days per month  35 ° C maximum wet bulb temperature exceedance  Gridbox mean of station percentages of days where the daily maximum Tw is equal to or exceeds 35 ° C 
TX  t_max  ° C  maximum dry bulb temperature  Gridbox mean of station month maxima of daily maxima T 
TXX  t_max_max  ° C  maximum maximum dry bulb temperature  Gridbox maximum of station month maxima of daily maxima T 
TX90p  t_max_90p  % days per month  90th percentile maximum dry bulb temperature exceedance  Gridbox mean of station percentages of days where the daily maximum T exceeds the climatological 90th percentile of daily maxima for the month 
TM90p  t_mean_90p  % days per month  90th percentile mean dry bulb temperature exceedance  Gridbox mean of station percentages of days where the daily mean T exceeds the climatological 90th percentile of daily means for the month 
TM10p  t_mean_10p  % days per month  10th percentile mean dry bulb temperature exceedance  Gridbox mean of station percentages of days where the daily mean T is lower than the climatological 10th percentile of daily means for the month 
TN10p  t_min_10p  % days per month  10th percentile minimum dry bulb temperature exceedance  Gridbox mean of station percentages of days where the daily minimum T is lower than the climatological 10th percentile of daily minima for the month 
TN  t_min  ° C  Minimum daily minima dry bulb temperature  Gridbox mean of station month minima of daily minima T 
TX25  t_max_ex25  % days per month  25 ° C maximum dry bulb temperature exceedance  Gridbox mean of station percentages of days where the daily maximum T is equal to or exceeds 25 ° C 
TX30  t_max_ex30  % days per month  30 ° C maximum dry bulb temperature exceedance  Gridbox mean of station percentages of days where the daily maximum T is equal to or exceeds 30 ° C 
TX35  t_max_ex35  % days per month  35 ° C maximum dry bulb temperature exceedance  Gridbox mean of station percentages of days where the daily maximum T is equal to or exceeds 35 ° C 
TX40  t_max_ex40  % days per month  40 ° C maximum dry bulb temperature exceedance  Gridbox mean of station percentages of days where the daily maximum T is equal to or exceeds 40 ° C 
TX45  t_max_ex45  % days per month  45 ° C maximum dry bulb temperature exceedance  Gridbox mean of station percentages of days where the daily maximum T is equal to or exceeds 45 ° C 
TX50  t_max_ex50  % days per month  50 ° C maximum dry bulb temperature exceedance  Gridbox mean of station percentages of days where the daily maximum T is equal to or exceeds 50 ° C 
TN18  t_min_ex18  % days per month  18 ° C minimum dry bulb temperature exceedance  Gridbox mean of station percentages of days where the daily minimum T is equal to or exceeds 18 ° C 
The ASCII good station list file contains a WMO identifier (digits 05 (a6)), a WBAN identifier (digits 610 (a5)), a latitude (digits 1119 (f9.4)), a longitude (digits 2029 (f10.4)), an elevation in metres (digits 2935 (f7.1)), space, a country ID (digits 3739 (a2)), space, and a name (digits 4172 (a32)).
NetCDF gridded file field  Description  Dimensions 

*_abs  Gridbox means of station monthly index values  72 by 36 by 584 
*_anoms  Gridbox means of station monthly anomalies from station 19912020 climatology period means (only climatological mean subtracted, not standardised)  72 by 36 by 584 
*_std  Gridbox standard deviations of station monthly anomalies from station 19912020 climatology period means (only climatological mean subtracted, not standardised)  72 by 36 by 584 
*_clims  Gridbox mean of station month climatological means over the 19912020 period  72 by 36 by 12 
*_clim_std  Gridbox mean of station month climatological standard deviations over the 19912020 period  72 by 36 by 12 
mean_n_stations  Total number of stations within the gridbox over entire record  72 by 36 
actual_n_stations  Actual number of stations within the gridbox for each time step  72 by 36 by 584 
HQ1  Score for number of stations within gridbox: 1 station = 1, >1 stations = 0.  72 by 36 by 584 
HQ2  Score for inhomogeneity density within gridbox: 1 per station = 2, 01 per station = 1, 0 per station = 0.  72 by 36 by 584 
HQ3  Score for VERY LARGE (>2 ° C) inhomogeneity density within gridbox: 1 per station = 10, 01 per station = 19 scaled linearly, 0 per station = 0.  72 by 36 by 584 
HQ4  Score for LARGE (12 ° C) inhomogeneity density within gridbox: 1 per station = 5, 01 per station = 14 scaled linearly, 0 per station = 0.  72 by 36 by 584 
HQ5  Score for MODERATE (0.51 ° C) inhomogeneity density within gridbox: 1 per station = 3, 01 per station = 12 scaled linearly, 0 per station = 0.  72 by 36 by 584 
HQ6  Score for SMALL (00.5 ° C) inhomogeneity density within gridbox: 1 per station = 0, 01 per station = 0, 0 per station = 0.  72 by 36 by 584 
HQ7  Mean adjustment magnitude within gridbox: >= 2 ° C = 10, 12 ° C = 49 scaled linearly, 0.51 ° C = 23 scaled linearly, 00.5 ° C = 1, 0 ° C = 0.  72 by 36 by 584 
HQ8  Mean absolute adjustment magnitude within gridbox: No score  additional indicator as required.  72 by 36 by 584 
HQ Flag  Homogenisation Quality Flag for the gridbox month: >= 10 = very poor quality, 79 = poor quality, 56 = moderate quality, 14 = good quality, 0 = excellent quality.  72 by 36 by 584 
latitude  Latitude in 5°  72 by 36 
longitude  Longitude in 5°  72 by 36 
time  Gregorian: Days since 1st January 1973 00:00:00  584 
months  112  12 
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