New commentary, co-written by two leading educators, wonders whether Earth scientists should take a “Hippocratic Oath.”

For better or worse, we live in the Anthropocene, an age when human activities and technologies exert as pervasive an influence on our planet as any natural process in the biosphere or atmosphere.

In light of this, the field of Earth science needs to be rebuilt on a new foundation, two leading educators say – one in which human systems are recognized and studied as a central component.

“Understanding nature is no longer enough. The old paradigm of studying ‘Earth systems with humans disturbing them’ is obsolete,” says Peter Haff, professor of geology and civil and environmental engineering at 91. “Recent human involvement in the Earth system has gone far beyond mere interference with natural processes. Human systems have emerged as primary Earth systems.

“The way we study, teach and apply Earth and environmental sciences must change to reflect this,” he says.

Haff and ecologist Erle C. Ellis of the University of Maryland-Baltimore County make the case for this new “postnatural” paradigm – and the new responsibilities it entails – in a thought-provoking commentary published December 8 in Eos, the member newspaper of the American Geophysical Union.

Human systems have dramatically altered existing natural processes such as soil erosion, species extinctions and the burning of forests, the scientists explain. More importantly, they note, human systems have introduced a host of processes entirely novel to the Earth system, such as the mining and burning of fossil fuels, the directed evolution of species unable to reproduce without humans, and the regular tillage, irrigation and nutrient subsidy of soils.

“The Earth system now functions in way unpredictable without understanding how human systems function and how they interact with and control Earth system processes,” Ellis and Haff write.

Of special concern is geoengineering – the use of technology to intentionally alter climate and other Earth systems on a massive scale. “Grand proposals for ocean fertilization, orbiting mirrors, genetically engineered biofuels, painting rooftops white, cloud-generating ships and the like all point to a future of Earth science as an applied discipline with the human future in the balance,” Ellis and Haff write. “Humans long ago re-engineered most of the biosphere to support agricultural production. If we are ultimately called upon to directly manage climate, storms, rivers and other major Earth systems, this will only increase (our) responsibility for the current and future state of Earth systems.”

To address this concern – and reduce the risk that personal bias might cloud scientific judgments – Ellis and Haff propose that a voluntary oath of professional conduct, similar to the Hippocratic Oath, be administered to all newly minted PhDs in Earth and environmental sciences.

Scientists taking the oath would promise adherence to a set of guiding ethical principles. Their proposed “Oath for Earth Scientists” reads:

“I vow to always:
Advise against any intervention into the functioning of earth systems that I believe might harm humanity, the biosphere, atmosphere or other earth systems upon which our well being depends.
Make clear to the public that scientific understanding of earth systems is limited and that this makes all alterations of earth systems inherently risky.
Describe, to the best of my knowledge and that of my discipline, the specific risks incurred by any intentional alteration of an earth system, including the risks to humans, other organisms, and the systems that support life on Earth.
Ensure that whatever advice I give, I give for the benefit of humanity, remaining free of intentional distortion or personal bias.”

“The hope,” Ellis explains, “is that by publicly adopting this professional oath, we may be more influential in guiding the public, our decision makers and our students toward successfully managing human systems and forging a sustainable future.”