> Home > HadISDH >

HadISDH data download - version 1.0.0.2022f

The current version of HadISDH.extremes is 1.0.0.2022f. 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 1991-2020 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 0-5 (a6)), a WBAN identifier (digits 6-10 (a5)), a latitude (digits 11-19 (f9.4)), a longitude (digits 20-29 (f10.4)), an elevation in metres (digits 29-35 (f7.1)), space, a country ID (digits 37-39 (a2)), space, and a name (digits 41-72 (a32)).

Product	Description	Data file

HadISDH.extremes*.1.0.0.2022f grids NetCDF	Land surface grids	HadISDH.extremesTwX.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTwXX.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTwX90p.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTwM90p.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTwM10p.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTwN10p.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTwN.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTwX25.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTwX27.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTwX29.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTwX31.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTwX33.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTwX35.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTX.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTXX.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTX90p.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTM90p.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTM10p.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTN10p.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTN.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTN18.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTX25.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTX30.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTX35.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTX40.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTX45.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc, HadISDH.extremesTX50.1.0.0.2022f_FLATgridHOM5by5_anoms9120.nc,
HadISDH.extremes*.1.0.0.2022f good station list ASCII	Stations by WMO identifier, latitude, longitude and elevation	PosthomogIDPHAtw_max_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAtw_max_max_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAtw_max_90p_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAtw_mean_90p_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAtw_mean_10p_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAtw_min_10p_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAtw_min_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAtw_max_ex25_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAtw_max_ex27_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAtw_max_ex29_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAtw_max_ex31_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAtw_max_ex33_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAtw_max_ex35_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAt_max_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAt_max_max_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAt_max_90p_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAt_mean_90p_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAt_mean_10p_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAt_min_10p_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAt_min_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAt_all_ex18_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAt_max_ex25_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAt_max_ex30_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAt_max_ex35_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAt_max_ex40_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAt_max_ex45_anoms9120_goodsHadISDH.1.0.0.2022f.txt, PosthomogIDPHAt_max_ex50_anoms9120_goodsHadISDH.1.0.0.2022f.txt

NetCDF gridded file field	Description	Dimensions

*_abs	Gridbox means of station monthly index values	72 by 36 by 600
*_anoms	Gridbox means of station monthly anomalies from station 1991-2020 climatology period means (only climatological mean subtracted, not standardised)	72 by 36 by 600
*_std	Gridbox standard deviations of station monthly anomalies from station 1991-2020 climatology period means (only climatological mean subtracted, not standardised)	72 by 36 by 600
*_clims	Gridbox mean of station month climatological means over the 1991-2020 period	72 by 36 by 12
*_clim_std	Gridbox mean of station month climatological standard deviations over the 1991-2020 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 600
HQ1	Score for number of stations within gridbox: 1 station = 1, >1 stations = 0.	72 by 36 by 600
HQ2	Score for inhomogeneity density within gridbox: 1 per station = 2, 0-1 per station = 1, 0 per station = 0.	72 by 36 by 600
HQ3	Score for SMALL (0-0.5 ° C) inhomogeneity density within gridbox: 1 per station = 0, 0-1 per station = 0, 0 per station = 0.	72 by 36 by 600
HQ4	Score for MODERATE (0.5-1 ° C) inhomogeneity density within gridbox: 1 per station = 3, 0-1 per station = 1-2 scaled linearly, 0 per station = 0.	72 by 36 by 600
HQ5	Score for LARGE (1-2 ° C) inhomogeneity density within gridbox: 1 per station = 5, 0-1 per station = 1-4 scaled linearly, 0 per station = 0.	72 by 36 by 600
HQ6	Score for VERY LARGE (>2 ° C) inhomogeneity density within gridbox: 1 per station = 10, 0-1 per station = 1-9 scaled linearly, 0 per station = 0.	72 by 36 by 600
HQ7	Mean adjustment magnitude within gridbox: >= 2 ° C = 10, 1-2 ° C = 4-9 scaled linearly, 0.5-1 ° C = 2-3 scaled linearly, 0-0.5 ° C = 1, 0 ° C = 0.	72 by 36 by 600
HQ8	Mean absolute adjustment magnitude within gridbox: No score - additional indicator as required.	72 by 36 by 600
HQ Flag	Homogenisation Quality Flag for the gridbox month: >= 10 = very poor quality, 7-9 = poor quality, 5-6 = moderate quality, 1-4 = good quality, 0 = excellent quality.	72 by 36 by 600
latitude	Latitude in 5°	72 by 36
longitude	Longitude in 5°	72 by 36
time	Gregorian: Days since 1st January 1973 00:00:00	600
months	1-12	12

NetCDF station file field	Description	Dimensions

*_abs	Monthly mean value	600
*_anoms	Monthly mean anomaly from the 1991-2020 climatology period (climate anomaly, not standardised)	600
*_stds	Standard deviation of all station monthly mean anomalies within the gridbox for each month	600
*_clims	Monthly climatologies over the 1991-2020 period	12
times	Months since January 1973	600
months	1-12	12

-->

Commercial and media enquiries

You can access the Met Office Customer Centre, any time of the day or night by phone, fax or e-mail. Trained staff will help you find the information or products that are right for you.
Contact the Met Office Customer Centre