A new US report and a recent warning from 17,000 scientists adds to the chorus of those calling for climate action. On November 3, 2017, US government released its most significant and conclusive climate change report yet. The U.S. Global Change Research Program’s fourth National Climate Assessment (NCA4) is a comprehensive review of leading climate science that was compiled with contributions from 13 federal agencies under the direction of the National Oceanic and Atmospheric Administration (NOAA). Further, it was reviewed by the independent National Academy of Sciences and approved by the National Economic Council.
It clearly states that this is the warmest period in human history. It further states that this is due to human activity especially rising rates of greenhouse gas emissions. This study corroborates thousands of others that document melting glaciers, shrinking sea ice, rising sea levels, ocean acidification, and extreme weather.
Ten days later an open letter was issued by more than 15,000 scientists from 184 countries warning humanity about the dangers of climate change. The Alliance of Scientists letter was published in BioScience on November 13, 2017. The warning specifically said that humanity must change its ways in order to protect the planet. It specifically points to rising greenhouse gas emissions and deforestation.
The letter campaign was founded by William Ripple, a professor at Oregon State University’s College of Forestry. He found that over the last 25 years, there has been a 26.1 percent decline in the availability of fresh water per capita, and an increase in unsustainable marine fisheries. He also documented a 75.3 percent increase in ocean dead zones. He further concludes that forests are also declining and there is dwindling biodiversity. He also says that we have seen carbon emissions increase by 62 percent and this is driving global warming and climate change.
“We are in the throes of a mass extinction event that is anthropogenic,” said co-author Eileen Crist, a professor at Virginia Tech’s Department of Science and Technology in Society.
With the exception of ozone depletion, things have gotten substantially worse over the last 25 years. However, the fact that we were able to close ozone holes by finding alternatives to CFCs suggests that we may be able to transition away from fossil fuels and towards renewable sources of energy.
This is the second time in a quarter century that scientists have warned us to change our ways or face “widespread misery and catastrophic biodiversity loss”. “Humanity is not taking the urgent steps needed to safeguard our imperiled biosphere,” the letter reads.”Soon it will be too late to shift course away from our failing trajectory, and time is running out.” Let us hope that we heed this second notice as we may not have time for a third.