Lost Labour Index over Bangladesh (Hourly; 1980-2023)

The Lost Labour Index is an estimate of the amount of time per hour (in minutes) lost to outdoor workers due heat conditions. The index is adapted from work rest guidelines based on wet bulb globe temperatures. The work-rest guidelines are described by Brimicombe et al. (2023) and Jacklitsch et al. (2016), and summarised below. 

WBGT (°C) | Approximated work/rest cycles (minutes) 

>33           |  0/60 (Rest) 

30–33        | 15/45

28–30        | 30/30

25–28        | 30/15

23–25        | 45/15

<23           | 60/0 (No recommendations)

The Lost Labour Index is extrapolated from these work rest guidelines, assuming that if it is recommended that a worker must rest for n number of minutes every hour to remain safe in given temperature conditions, that labour/time is "lost" to the worker. The exact conversion is shown below: 

WBGT (°C) | Approximated work/rest cycles (minutes) | Lost Labour (minutes)

>33           |  0/60 (Rest)                                                 | 60

30–33        | 15/45                                                          | 45

28–30        | 30/30                                                          | 30

25–28        | 30/15                                                          | 20

23–25        | 45/15                                                          | 15

<23           | 60/0 (No recommendations)                      | 0

The datasets used to calculate the initial wet bulb globe temperatures (from which the Lost Labour Index was derived) were ERA5 Land (t2m, d2m, u10, v10, ssrd, ssr, strd, and strr variables) (Muñoz Sabater, 2019) and ERA5 (fdir variable - resampled to ERA5 Land spatial resolution) (Hersbach et al., 2020). The wet bulb globe temperature data was calculated using the Thermofeel library (Brimicombe et al. 2022). 

The Lost Labour Index in these files is calculated for a spatial area that covers the whole of Bangladesh (20-27 °N, 87-93 °E) and a temporal period of 1980-01-01T00:00 - 2023-12-31T23:00. The data has a spatial resolution of 0.1° and an hourly temporal resolution. Individual files are provided as zipped netCDFs for the decades of 1980-1989, 1990-1999, 2000-2009, and 2010-2019. Two separate files are provided for data from 2020-2022 and 2023 respectively. 

References

Brimicombe, C. et al. (2022) ‘Thermofeel: A python thermal comfort indices library’, SoftwareX, 18, p. 101005. Available at: https://doi.org/10.1016/j.softx.2022.101005.

Brimicombe, C. et al. (2023) ‘Wet Bulb Globe Temperature: Indicating Extreme Heat Risk on a Global Grid’, GeoHealth, 7(2), p. e2022GH000701. Available at: https://doi.org/10.1029/2022GH000701.

Hersbach, H., Bell, B., Berrisford, P., Hirahara, S., Horányi, A., Muñoz‐Sabater, J., Nicolas, J., Peubey, C., Radu, R., Schepers, D., Simmons, A., Soci, C., Abdalla, S., Abellan, X., Balsamo, G., Bechtold, P., Biavati, G., Bidlot, J., Bonavita, M., De Chiara, G., Dahlgren, P., Dee, D., Diamantakis, M., Dragani, R., Flemming, J., Forbes, R., Fuentes, M., Geer, A., Haimberger, L., Healy, S., Hogan, R.J., Hólm, E., Janisková, M., Keeley, S., Laloyaux, P., Lopez, P., Lupu, C., Radnoti, G., de Rosnay, P., Rozum, I., Vamborg, F., Villaume, S., Thépaut, J-N. (2017): Complete ERA5 from 1940: Fifth generation of ECMWF atmospheric reanalyses of the global climate. Copernicus Climate Change Service (C3S) Data Store (CDS). DOI: 10.24381/cds.143582cf

Jacklitsch, B., Williams, J., Musolin, K., Coca, A., Kim, J.-H., & Turner, N. (2016). Criteria for a recommended standard: Occupational exposure to heat and hot environments.

Muñoz Sabater, J. (2019): ERA5-Land hourly data from 1950 to present. Copernicus Climate Change Service (C3S) Climate Data Store (CDS). DOI: 10.24381/cds.e2161bac