Supplement code for ERA5 and IAGOS analysis, and along-track contrail distribution; quantile mapping bias-correction; temporal and spatial distributions of contrail formation potential and overlap; contrail climatologies, and contrail morphology.
This brief documentation accompanies two manuscripts:
- "Correction of temperature and relative humidity biases in ERA5 by bivariate quantile mapping: Implications for contrail classification."
and
- "Distribution and morphology of non-persistent and persistent contrail formation areas in ERA5.".
Both will be / are submitted to the journal Atmospheric Chemistry and Physics (ACP)
Please note. The provided code sections are for traceability purposes only. The code can only be used by others with major modifications. Generated data is not provided here.
ERA5 data of temperature, relative humidity, wind speed, and cloud fraction were download from the ERA5 data catalog (https://doi.org/10.24381/cds.f17050d7). Due to the distribution of IAGOS flights, the focus of the analysis is on a domain between 30°N and 70°N, where most of the IGAOS observations are available. These latitudes were selected similar to Petzold et al 2020.
The data was downloaded with the following script: ERA5_data_download.py
It is noted that the utilized python interface and downloads from the ERA5 data base require a registration on the CDS homepage: https://cds.climate.copernicus.eu/cdsapp#!/home. To register and to obtain an identification number please follow the instructions given on the CDS homepage.
Extraction of temperature, relative humidity, wind components, and fraction of cloud cover from ERA5
ERA5 data is extracted along IAGOS flight trajectories. Flights from the years 2015 to 2021 are used. Extraction is performed with the nearest neighbor method by selecting the temporally and spatially closest ERA5 grid point. The code that was used to extract data from ERA5 with a 1 hour resolution is given here: A01_extract__along_flightpath_1h.py
The inventory of cumulative distribution functions CDFs are created with: A02_create_cdf.py
The pickled ERA5, IAGOS data, and CDFs are read with: A03_apply_2d_correction.py. This code also applies the quantile mapping corrections and includes the analysis that is presented in the manuscripts.
Vertical distributions of contrail formation potential and vertical overlap were created with: A06_era_3d.py
Climatologies of temperature, relative humidity, wind speed, and persistent contrail formation were created with: A07_monthly_crosssections.py
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., and Thépaut, J.-N.: The ERA5 global reanalysis, Q. J. Royal Meteorol. Soc., 146, 1999–2049, https://doi.org/10.1002/qj.3803, 2020.
Hersbach, H., Bell, B., Berrisford, P., Biavati, G., Horányi, A., Muñoz Sabater, J., Nicolas, J., Peubey, C., Radu, R., Rozum, I., Schepers, D., Simmons, A., Soci, C., Dee, D., and Thépaut, J.-N.: ERA5 monthly averaged data on single levels from 1940 to present., https://doi.org/10.24381/cds.f17050d7, 2023
Petzold, A., Neis, P., Rütimann, M., Rohs, S., Berkes, F., Smit, H. G. J., Krämer, M., Spelten, N., Spichtinger, P., Nédélec, P., and Wahner, A.: Ice-supersaturated air masses in the northern mid-latitudes from regular in situ observations by passenger aircraft: vertical distribution, seasonality and tropospheric fingerprint, Atmos. Chem. Phys., 20, 8157–8179, https://doi.org/10.5194/acp-20-8157-2020, 2020.
Rap, A., Forster, P. M., Jones, A., Boucher, O., Haywood, J. M., Bellouin, N., and De Leon, R. R.: Parameterization of contrails in the UK Met Office Climate Model, J. Geophys. Res. Atmos., 115, https://doi.org/https://doi.org/10.1029/2009JD012443, 2010.
Schumann, U.: On conditions for contrail formation from aircraft exhausts, Meteorologische Zeitschrift, 5, 1996.
Teoh, R., Schumann, U., Voigt, C., Schripp, T. Shapiro, M., Engberg, Z., Molloy, J., Koudis, G., and Stettler, M. E. J.: Targeted Use of Sustainable Aviation Fuel to Maximize Climate Benefits, Environ. Sci. Technol., https://doi.org/10.1021/acs.est.2c05781, 2022b.
Wolf, K., Bellouin, N., and Boucher, O.: Long-term upper-troposphere climatology of potential contrail occurrence over the Paris area derived from radiosonde observations, Atmos. Chem. Phys., 23, 287–309, https://doi.org/10.5194/acp-23-287-2023, 2023