1. Department of Civil and Environmental Engineering University of Michigan Ann Arbor Michigan USA
2. Department of Global Ecology Carnegie Institution for Science Stanford California USA
3. Now at Data Assimilation Research Section NCAR Boulder Colorado USA
4. European Centre for Medium‐Range Weather Forecasts Reading UK
5. NASA Goddard Space Flight Center Greenbelt Maryland USA
6. Earth System Research Laboratory NOAA Boulder Colorado USA
7. Cooperative Institute for Research in Environmental Science University of Colorado Boulder Colorado USA