1.
Johan Rockström – 2
Prof. Dr. Johan Rockström
Director, Potsdam Institute for Climate Impact Research
Professor in Earth System Science, University of Potsdam
The hydrological cycle as a global common good
WMO Roundtable on Financing Water
February 7, 2023 (pre-recorded)

2.
4
Humanity is entirely dependent on the
balance of 9 Planetary Boundaries…
…But today we are over-exploiting
many of them
CLIMATE
CHANGE
NOVEL
ENTITIES
BIOSPHERE
INTEGRITY
LAND SYSTEM
CHANGE
STATOSPHERIC
OZONE DEPLETION
FRESHWATER
CHANGE
ATMOSPHERIC
AEROSOL
LOADING
BIOGEOCHEMICAL
FLOWS
OCEAN
ACIDIFICATION
Source: Richardson et al. Work in Progress.
Source: Stockholm Resilience Centre, Sept 2022

3.
Global environmental change is fundamentally
shifting water partitioning / appropriation

4.
PB3.0 Ongoing Work
BLUE
GREEN

5.
Global environmental change is shifting precipitation
Source: Tebaldi et al 2021

6.
Global environmental change is shifting terrestrial precipitation
Source: IPCC AR6 table 8.1, derived from P [mm day -1]
assuming 145 Mkm2 terrestrial land area Source: Tebaldi et al 2021

7.
Source: Global Carbon Project
Terrestrial sequestered carbon is only possible with green water.

8.
Source: Global Carbon Project
Terrestrial sequestered carbon is only possible with green water.

9.
Moisture feedback creates inter-dependence between nations
Keys 2016

10.
Moisture recycling connects us globally, management is regionally focused.
Keys 2016
Global
Regional
Local

11.
Moisture feedback creates inter-dependence between nations
Figure: PIK

12.
Moisture feedback creates inter-dependence between nations
Figure: PIK

13.
Moisture feedback creates inter-dependence between nations
Figure: PIK

14.
Moisture feedback creates inter-dependence between nations
Figure: PIK

15.
Moisture feedback creates inter-dependence between nations
Ukraine
Nigeria
Netherlands
India
Germany
DR Congo
China
Brazil
Argentina
Ukraine
Nigeria
Netherlands
India
Figure: PIK

16.
Global Hydrological Cycle is a global
common good
- It connects all scales and Earth system functions
- All citizens and the world economy depends on stable water
flows
- Atmospheric rivers connect countries in the world

17.
THANK YOU!
www.pik-potsdam.de
@PIK_Climate |@PIK_Klima