Greenhouse Gas Emissions Could Spell Disaster for Mankind by 2100

Greenhouse Gas Emissions Could Spell Disaster for Mankind by 2100

by Dr. Kaushik Bharati on Nov 21 2018 1:03 PM
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  • Greenhouse gas emissions can have a profound effect on climate change, which can have adverse effects on human health, food and water availability, infrastructure, security, and economy
  • If greenhouse gas emissions remain unchecked, it will lead to cumulative number of climate hazards, which could affect humanity so adversely that human survival may become impossible by 2100
  • Prevention is only possible by taking immediate action to mitigate the emission of greenhouse gases
Greenhouse gas emissions can have adverse effects on climate change, which can have detrimental effects on human health, food and water availability, infrastructure, security, and economy. A new study carried out by researchers at the University of Hawaii at Mānoa, indicates that if the emission of greenhouse gases continues without immediate remedial measures, the consequences for mankind within less than a century could prove to be catastrophic.
The study, published in Nature Climate Change, is the most comprehensive assessment so far on the cumulative effects of global greenhouse gas emissions on multiple climate hazards that can seriously impact human health.

The lead author of the study is Dr. Camilo Mora, PhD, Associate Professor, Department of Geography and Environment, College of Social Sciences, University of Hawaii at Mānoa. There were a total of 23 co-authors, including veteran climate scientists, many of whom are members of the Intergovernmental Panel on Climate Change (IPCC).


Why is the Study So Unique?

The uniqueness of the study stems from the fact that until now, except for a few studies, climate hazards arising from greenhouse gas emissions have been studied individually. However, studying these hazards individually will miss out on the larger picture arising from the additive effects of the many climate hazards that impact humanity.


Study Design

This was a systematic review in which the researchers meticulously analyzed thousands of peer-reviewed scientific papers and over 3,000 documented examples along with supporting papers. The study involved exhaustive data mining and this was possible due to the technological skills and abilities of Dr. Mora’s graduate students, who analyzed vast amounts of big data.


Study Findings

The study found 467 ways by which the following parameters have already been affected by hazards arising from climate change:
  • Human Health: Malnutrition, pathogenic diseases, chemical toxicity, addiction, stress, vector-borne diseases, accidents/injuries, mental health, air quality hazard, prenatal/child health, food poisoning, famines, post-traumatic stress disorder, educational attainment, life satisfaction, recreation, solastalgia, life-expectancy, death, disability.
  • Food: Contamination, nutritional value, food prices, food shortages, agriculture, aquaculture, marine/freshwater fisheries, livestock.
  • Water: Quality, quantity, scarcity, run-off/flow.
  • Security: Migration, displacement, violence, criminal/aggressive behavior, conflict, social order, gender inequality, military build-up, democracy, evacuation.
  • Economy: Jobs, labor productivity, property damage costs, tourism, health care costs, land value, relief effort costs, insurance, economic growth/loss, adaptation costs, prices.
  • Infrastructure: Health/energy infrastructure, bridge, shelter, transport (road/railroad/air), electricity, buildings, irrigation, land loss, coastal barrier, communications, landslides, navigation, ports, dams, levee, wastewater.
All of the above parameters have been affected by the following climatic hazards:
  • Warming
  • Natural Cover Change
  • Heatwaves
  • Precipitation
  • Drought
  • Floods
  • Fires
  • Storms
  • Sea Level
  • Ocean Climate Change

Implications of the Study

Dr. Camilo Mora indicated that greenhouse gas emissions pose a major threat to all of mankind, since these emissions are capable of simultaneously intensifying many hazards that have proven to be harmful in the past. Importantly, by 2100, the concurrent occurrence of these hazards will be so intensified that it will be most difficult for humans to cope.

For instance, in 2100, the Atlantic coast of Brazil will face five climate hazards, while New York and Mexico City will each face four. In the same year, Los Angeles and Sydney will each experience three concurrent climate hazards. Therefore, there is an urgent need to stop greenhouse gas emissions immediately.

In particular, sea level rise and extreme precipitation must be checked at all costs. However, even if strong preventive strategies are immediately implemented, the cumulative impact of the multiple climate hazards will be severe and will not discriminate between rich and poor countries. For tropical coastlines, its impact will be particularly devastating.

A very interesting and useful Web-App accompanies the paper by which users can see the cumulative climate hazards that can occur anywhere on the planet under various emission scenarios, from now till 2100.

Dr. Dawn J. Wright, PhD, Chief Scientist, Environmental Systems Research Institute (Esri), Redlands, California, USA, indicated that the study was highly compelling and clearly showed the dangers that the world faces from the threat of climate change and the urgency for implementing immediate remedial measures.

Expert Comments

“Our health depends on multiple factors, from clean air and water, to safe food and shelter and more,” said co-author Dr. Jonathan Patz, MD, MPH, Professor and Director, Global Health Institute, University of Wisconsin-Madison, USA. “So, without a real systems approach to climate change impacts, we cannot adequately understand the full risks. If we only consider the most direct threats from climate change, for example heatwaves or severe storms, we inevitably will be blindsided by even larger threats that, in combination, can have even broader societal impacts.”

Dr. Michael E. Mann, PhD, Distinguished Professor of Atmospheric Science, Department of Meteorology and Atmospheric Science, Penn State University, USA, who was not involved in the study, said: “This new research provides rigorous, quantitative support for a point we have emphasized for some time: the costs of inaction greatly outweigh the costs of taking action on climate change. It also provides robust support for another key point: we can still reduce future damage and suffering if we act quickly and dramatically to reduce carbon emissions.”

“The collision of cumulative climate hazards is not something on the horizon, it is already here,” said Dr. Mora. “Co-occurring and colliding climate hazards are already making headlines worldwide. Last year, for instance, Florida recorded extreme drought, record high temperatures, over 100 wildfires, and the strongest ever recorded hurricane in its Panhandle: the category 4 Hurricane Michael. Likewise, California is currently experiencing ferocious wildfires and one of the longest droughts, plus extreme heatwaves this past summer.”

In this regard, Dr. Daniele Spirandelli, PhD, Department of Urban and Regional Planning, University of Hawaii at Mānoa, and the co-author of the study, indicated that the evidence of climate change on humanity was abundant, loud and clear. The major question, she believed, was that how many wake-up calls it would take to wake-up?


The authors concluded that the analysis clearly indicates that climate change poses an increased threat to humanity, which is likely to be severely aggravated if substantial and timely reductions of greenhouse gas emissions are not achieved.

  1. Broad threat to humanity from cumulative climate hazards intensified by greenhouse gas emissions - (