1. Potsdam Institute for Climate Impact Research, 14412 Potsdam, Germany
2. Department of Physics, Humboldt University Berlin, 12489 Berlin, Germany
3. Institute of Mathematics, Technical University of Berlin, 10587 Berlin, Germany
4. Department of Control Theory, Nizhny Novgorod State University, 606950 Nizhny Novgorod, Russia
5. Institute of Complex Systems and Mathematical Biology, University of Aberdeen, Aberdeen AB24 3FX, United Kingdom