Planetary Boundaries

Planetary Boundaries - global climate change management guidance for humans? 

Before moving on to investigating specific management skills for global climate change, I got interested in this idea of 'planetary boundaries' - let's explore this further!


Planetary boundaries
Planetary boundaries defines the "safe operating space for humanity with respect to the Earth system, associated with the planet's biophysical subsystems or processes" (Rockström et al., 2009). It is a recent approach introduced in science, proposing the preconditions for human development when environmental change and Earth's capacity to regulate conditions appropriate for human activities occurred during the Holocene. 
During the Holocene, planet earth had resilience to 'buffer' the disturbances caused by human developments; for example, half of the greenhouse gases emissions were taken up by the nature and much of the heat coming to the Earth were absorbed by the deep ocean. However, as humans have become the major force of change in planetary scale in current Anthropocene, planet earth starts to change and give positive feedbacks in various environments. To tackle this challenge, planetary boundary framework has been suggested. 

There are nine processes of Earth-system associated with major thresholds of the planet, including climate change, rate of biodiversity loss (terrestrial and marine), stratospheric ozone depletion, ocean acidification, global freshwater use, land use change, disturbances in nitrogen and phosphorus cycle, chemical pollution and atmospheric aerosol loading. Three out of nine boundaries are already transgressed currently (see Figure 1). 

Figure 1 - Planetary boundaries criteria - green shades are the proposed safe operating space for each of planetary systems and red wedges are the estimate of current position for each variable. Three systems' boundaries (Biodiversity loss rate, climate change and human interference with Nitrogen cycle) are already been exceeded currently. 
(Source: Rockström et al., 2009).

Studies on planetary boundaries suggest that if the threshold for earth-systems are exceeded, if will result in 'deleterious or potentially even disastrous consequences for humans' (Scheffer et al., 2001). 

Along with readings, I found and watched a TED talk by Johan Rockström, one of the leading scientists researching about the planetary boundaries; 

Are we bankrupting nature?  Johan Rockstrom at TEDxUppsalaUniversity (Source: https://www.youtube.com/watch?v=2Xc8WHtKBio)

During the talk, Johan mentions that us humans need to deeply consider not only about walking such huge 'transformation' that we are going through together, but also recognising that we are in a world where it reached the nature's saturation point and thus share remaining ecological space on Earth. Also, he suggests that it is time for humans to reconnect to the Biosphere, reversing the existing 'order' in human development and earth's environment - where humans are driving economic developments first and then reducing the environmental impacts - and moving onto the new paradigm of 'growth within limits'. 
I agreed to his thoughts and also thought that despite all those efforts to quantitatively and qualitatively define 'safe-operating' spaces of planet earth, if we humans do not start to change views looking at the planet and its values sustaining us, it will have only a little use in managing the degradation that is happening all over the world.  
We are very lucky to live within this diverse and rich biosphere where our society and economy can thrive, so now efforts for appreciating those spaces should be needed in such urgent situation. 




References:

Rockström, J., Steffen, W., Noone, K., Persson, Å., Chapin, F.S., Lambin, E.F., Lenton, T.M., Scheffer, M., Folke, C., Schellenhuber, H.J., Nykvist, B., De Wit, C.A., Hughes, T., Van Der Leeuw, S., Rodhe, H., Sörlin, S., Snyder, P.K., Costanza, R., Svedin, U., Falkenmark, M., Karlberg, L., Corell, R.W., Fabry V.J., Hansen, J., Walker, B., Liverman, D., Richardson, K., Crutzen, P., and Foley, J.A. 2009. A Safe Operating Space For Humanity. Nature. 461.7263: 472-475.

Scheffer, M., Carpenter, S. R., Foley, J. A., Folke C. & Walker, B. H. 2001. Catastrophic shifts in ecosystems. Nature 413: 591–596.