This repository contains the SEWA-MHWs dataset, which consists of daily fields of Marine heatwaves (MHWs) macroevents, daily fields of MHWs characteristics, and daily fields of relevant atmospheric variables over Southern Europe and Western Asia region. It contains also the codes to detect MHWs macroevents and their characteristics. The SEWA-MHWs dataset is derived from the European Space Agency (ESA) Climate Change Initiative (CCI) Sea Surface Temperature (SST) v2.1 dataset and it covers the 1981-2016 period. This dataset is presented and described in detail in the "Southern Europe and Western Asia Marine Heat Waves (SEWA-MHWs): a dataset based on macroevents" manuscript by Giulia Bonino, Simona Masina, Giuliano Galimberti, and Matteo Moretti submitted to Earth System Science Data journal (Bonino et al., 2022). This repository contains 3 compressed (*.zip) folders: A) MHWs: it contains daily fields of MHWs macroevents, daily fields of MHWs characteristics SEWA_labels.nc: daily fields of labels. Each unique label represents a macro event. SEWA_IndStart.nc: daily fields of MHWs index start. SEWA_IndPeak.nc: daily fields of MHWs index peak. SEWA_IndEND.nc: daily fields of MHWs index end. SEWA_Category.nc: daily fields of MHWs categories. SEWA_IntMAx.nc: daily fields of MHWs maximum intensity [°C]. SEWA_IntMean.nc: daily fields of MHWs mean intensity [°C]. B) CODES: Python notebooks to detect MHWs macroevents and their characteristics. MHWs_stl.ipynb to detect MHWs and their characteristics SEWA_LABEL.ipynb: to generate the MHWs macroevents MHWs_filter.ipynb: to filter out the smallest macroevents STL_MarineHeatwaves.py: it contains the function “detect_stl” to detect MHWs using STL method used in MHW_stl.ipynb. This function is a modification of the “detect” function in the marineHeatWaves package created by Eric Oliver (https://github.com/ecjoliver/marineHeatWaves). C) ATM: daily mean fields of relevant atmospheric variables taken from ERA5 (Hersbach et al., 2020, freely available at https://cds.climate.copernicus.eu/cdsapp#!/dataset/reanalysis-era5-single-levels?tab=overview). These data are subsets of the ERA5 dataset, after minimal post-processing manipulation. The area extracted for these meteorological parameters is slightly bigger than the SEWA region, allowing the investigation of remote influences and/or responses of these variables in relationship with MHWs macroevents. The covered area is from 10°N to 70°N in latitude and from 50°W to 80°E in longitude. The covered period is 1981-2016. SEWA_T2.nc: daily mean fields of 2 meter temperature [K]. “2m temperature” is the native variable name in ERA5 dataset. Unlike ERA5 dataset the data are provided as daily mean. SEWA_LAT.nc: daily mean fields of surface latent heat flux [W/m2]. “Surface latent heat flux” is the native variable name in ERA5 dataset. Unlike ERA5 the data are provided as daily mean and in W/m2 instead of J/m2. SEWA_SENS.nc: daily mean fields of surface sensible heat flux [W/m2]. “Surface sensible heat flux” is the native variable name in ERA5 dataset. Unlike ERA5 the data are provided as daily mean and in W/m2 instead of J/m2. SEWA_SLP.nc: daily mean fields of mean sea level pressure [Pa]. “Surface pressure” is the native variable name in ERA5 dataset. Unlike ERA5 the data are provided as daily mean. SEWA_WIND.nc: daily mean fields of 10 meter wind speed [m/s]. This variable is calculated from the wind components “10m u-component of wind” and “10m v-component of wind” of the ERA5 dataset. Unlike ERA5 the data are provided as daily mean. SEWA_SW.nc: daily mean fields of incoming solar radiation [W/m2]. “Surface solar radiation downwards” is the native variable name in ERA5 dataset. Unlike ERA5 the data are provided as daily mean and in W/m2 instead of J/m2. REFERENCES: Bonino, G., Masina, S., Galimberti, G., & Moretti, M. (2022). Southern Europe and Western Asia marine heat waves (SEWA-MHWs): a dataset based on macro events. Earth System Science Data Discussions, 1-19. Hersbach, H., Bell, B., Berrisford, P., Hirahara, S., Horányi, A., Muñoz-Sabater, J., Nicolas, J., Peubey, C., Radu, R., Schepers, D., et al.: The ERA5 global reanalysis, Quarterly Journal of the Royal Meteorological Society, 146, 1999–2049, 2020.

This research has been funded by the European Space Agency (ESA) as part of the FEVERSEA Climate Change Initiative (CCI) fellowship (ESA ESRIN/Contract No. 4000133282/20/I/NB).