observational method

Pepin, N., Bradley, R. S., Diaz, H. F., Baraer, M., Caceres, E. B., Forsythe, N., et al. (2015). Elevation-dependent warming in mountain regions of the world. Nature Climate Change. http://doi.org/10.1038/nclimate2563
Beck, H. E., Vergopolan, N., Pan, M., Levizzani, V., Van Dijk, A. I. J. M., Weedon, G. P., et al. (2017). Global-scale evaluation of 22 precipitation datasets using gauge observations and hydrological modeling. Hydrology And Earth System Sciences. http://doi.org/10.5194/hess-21-6201-2017
Schultz, M. G., Schröder, S., Lyapina, O., Cooper, O. R., Galbally, I., Petropavlovskikh, I., et al. (2017). Tropospheric Ozone Assessment Report: Database and metrics data of global surface ozone observations. Elementa. http://doi.org/10.1525/elementa.244