Critical components missing from current climate change models, says global study

An international team of distinguished scientists, including five members of national academies have argued that there are crucial components missing from current climate models that inform about environmental, climatic and economic policies.

This new study shows the relationship between people and the planet shows that the climate change is one of the factors that threats Earth's capacity to support human life.

The article was published in the journal National Science Review.

The study describes how the growth in resource use, land-use change, emissions and pollution has made humanity the dominant driver of change in most of the Earth's natural systems and these changes are having drastic effects on humans with serious and costly consequences.

The authors say that current estimates of the impact of climate change do not connect human variables like demographics, economic growth, inequality, economic growth and migration, with planetry changes. That makes all the current models miss the important feedbacks in real Earth-human system, especially those that may result in unexpected outcomes.

Furthermore, the authors argue that some of the existing models are unreliable. The United Nations projections of a relatively stable population for the whole of the developed world depend, on dramatic and highly unlikely declines projected in a few key countries. For example, Japan must decline by 34%, Germany by 31% and Russia by about 30% for the projected stability in total developed country population to be born out. 12 countries in addition, often highlighted for their low birth rates, like Italy and Spain, are not projected to decline by even 1% for decades.

"Current models are likely to miss critical feedback in the combined Earth-Human system. It would be like trying to predict El Niño with a sophisticated atmospheric model but with the Sea Surface Temperatures taken from external, independent projections by, for example, the United Nations. Without including the real feedbacks, predictions for coupled systems cannot work; the model can get away from reality very quickly," said co-author Eugenia Kalnay, professor of Atmospheric and Oceanic Science at University of Maryland.

In this new research, the authors present extensive evidence of the need for a new type of model that incorporates the feedbacks that the earth system has on humans, and propose a framework for future modeling that would serve as a more realistic guide for policymaking and sustainable development.