A Holistic Understanding of the Earth
Why Earth System Science is crucial to our understanding of the environment.
Scientific inquiry has proven that it is possible to regard the Earth as a complex system. ‘From space we can view the Earth as a whole system, observe the net results of complex interactions, and begin to understand how the planet is changing in response to natural and human influences (Excerpt from NASA’s Earth Science Enterprise Strategy, 2003).’ The interactions between the planet’s different environmental spheres show that they exist interdependently.
It is becoming increasingly clear that the problems and challenges presenting themselves in the environmental sphere are highly interlinked, complex, and multidisciplinary. In pursuit of a sustainable future on a planet consisting of finite resources, it has been posited by various academics that ‘systems thinking competence’ will be necessary for humanity to achieve a workable way of sustainably existing on its planetary host.
In nature, everything is about interactions. Forests consist of complex feedback relations between trees, fungi, and bacteria. Butterflies exist because of interactions between plants, animals, fungi, and protozoa. Life exists in symbiosis. Earth System Science seeks to recognize this by drawing biologists, ecologists, geologists, physical geographers, and environmental scientists into interdisciplinary research with economists, technologists, and policy makers together to forge a holistic understanding of the Earth.
The argument in favor of regarding the Earth as a system is clear. The authors of Limits to Growth (1972, 2004) used the systems approach because it enabled them to ‘approach problems in new ways and discover unsuspected options.’ They consider the systems perspective to be the most important part of their worldview.
The systems approach can be used to gather proxy and documentary evidence of past changes in the global physical environment and, through their interpretation and supercomputer modeling, to enable us to predict, respond to, and sometimes manage future changes.
Regarding the Earth as a system helps scientists to make future predictions about the changing climate. It has been central to the work of the IPCC in compiling its assessment reports of the effects of human activity on the environment since 1990. Researchers from various fields can benefit from the systems approach by seeing how their pieces of research relate to a larger puzzle.
As knowledge of the entire system increases and the nature of the interactions becomes clearer, data modeling can give a more accurate picture of the effects of various forcings and feedbacks in the climate. This approach has enabled scientists to link the changing ozone concentration over Antarctica with the industrial production of refrigerants in the northern hemisphere; to make the connection between atmospheric composition and air quality; and to understand how deforestation affects rainfall, evapotranspiration, and cloud cover.
It is difficult to criticize the pursuit of a holistic understanding of the Earth if one subscribes to the scientific method. However, there are concerns which arise from studying the Earth as a system. Our knowledge of the Earth is rapidly evolving, as is our knowledge of our own brains. Despite this, conclusions are regularly drawn from bodies of evidence that are incomplete. The Gaia hypothesis (Gaia) is an example of this which has ignited much academic debate.
Gaia proposes that a feature of the Earth system is that atmospheric homeostasis is maintained by and for the biosphere. Lovelock and Margulis (1974) contend that, because life has been present on Earth for a long period and has survived various alterations in the Earth’s radiation environment, the biosphere must have some control over the planetary environment to keep it habitable. This posits the atmosphere as an extension of the biosphere, a biocentric view.
Without the biosphere, the atmosphere would be closer to that of Mars and Venus and render the Earth inhospitable to life. This is true, but it also goes that without the atmosphere the biosphere would never have come into existence, a point which Lovelock conveniently passes over. Gaia is correct in asserting that organisms are not simply passive consumers of the Earth’s atmosphere and that they actively contribute to it, but to the extent that the biota is piloting the craft, they are flying blind!
Systems that tend towards equilibrium can seem to have some intent behind them. Ideas like Gaia are attractive to human beings because we are inclined to place ourselves at the center of the universe. The universe seemed far more accommodating back before it was discovered that not everything revolved around us.
Douglas Adams wrote of the sentient puddle waking up to find that it’s world seemed to fit it so precisely that it must have been made specifically for the puddle. Adams’ sentient puddle is extinguished by the Sun but remains ignorant of its fate until it ceases to exist. It is important that the application of systems thinking to environmental science does not lead to a similar trap and that knowledge continues to expand.
Another issue with the study of the Earth as a system is the assumption that the Earth operates in a way that is conceivable to the human mind and science. If certain areas of the system start displaying chaotic traits, then the environmental monitoring and modeling techniques used by scientists to enhance their understanding of the Earth will fall apart. The accuracy of scientific data can only be as good as the models used to compile it. Those models are designed by human beings with a finite brain capacity, who are drawn towards patterns and logic.
