The planet was at least one degree cooler when our ancestors created these pictograms near the Green River in Colorado about 700 to 2,000 years ago. (Brent Roraback photo)
While the world’s leading coalition of climate scientists says the planet is warming faster than ever, with dire human consequences, it also stresses that quick, aggressive measures to reduce emissions of heat-storing pollutants could stabilize temperatures within decades.
On Monday the United Nations Intergovernmental Panel on Climate Change (IPCC) published its sixth assessment report on the causes, effects and effects of global warming.
Some of the key messages:
- Human-made emissions of carbon dioxide, methane, and other gases have warmed the planet 1.1 degrees Celsius since the late 19th century, and temperatures could potentially soar to 1.5 degrees Celsius in the next 10-20 years.
- The earth is the warmest in more than 125,000 years. Carbon dioxide levels in 2019 were the highest in 2 million years.
- Scientists are more confident than ever that they are linking changes such as rising sea levels, melting glaciers, extreme temperature events, extreme storms and rain events, droughts and fires to climate change.
- If we can reduce our CO2 emissions enough to take more carbon out of the atmosphere than we put into it, we could gradually reverse the warming. But rising seas are a different matter – it might take “several centuries up Millennia until the global mean sea level reverses course. ”
The report was produced by 234 authors from 66 countries, including Kyle Armor, associate professor and climate scientist at the University of Washington, Richard Feely of NOAA Pacific Marine Environmental Laboratory, and Alan Mix of Oregon State University.
Armor told the Seattle Times that climate change is affecting every region of the world.
“Climate change is really widespread and intensifying, and many of the changes have been unprecedented for thousands of years,” said Armor.
The number that sticks in my memory is the potential to see a rise of 1.5 degrees Celsius in just a decade. With a rise of just over 1 degree in the last century and more, my home region in the Pacific Northwest was already rocked last June by drought, nightmarish forest fires and a surreal heat dome that set previously unthinkable temperature records for an area known for its muddy, mossier Shine.
What if we go up by almost half in such a short time?
The authors of the IPCC report project the likely degrees of warming that are possible depending on the amount of greenhouse gas emissions. Their models use different scenarios, ranging from the most optimistic with the largest cuts (SSP1-1.9) to the smallest cuts (SSP5-8.5). (Graphic from the Sixth Assessment Report of the IPCC, summary for decision-makers)
The IPCC report puts a stronger focus on the importance of setting and achieving ambitious short-term CO2 reduction targets. The governments of the world will meet this autumn in Glasgow for the UN Climate Change Conference of the Parties (COP26) to set reduction targets for their nations.
In the northwest, tech giants have set their own climate agendas.
- Microsoft remains the leader with a goal of becoming carbon negative by 2030. In January, the company announced that it had reduced its CO2 emissions by 6% from 11.6 million tons to 10.9 million tons. It also paid for the removal of an additional 1.3 million tons of carbon from the atmosphere.
- Amazon aims to be CO2 neutral by 2040. Last year, the company announced that its emissions rose by as much as 15% from 2018 to 2019. Amazon was responsible for 51.2 million tons of carbon dioxide, an amount roughly equivalent to Singapore’s footprint. The company continues to invest in renewable energy projects and is the largest corporate renewable energy buyer in the US and Europe.
- Amazon and Microsoft both backed some major Washington State climate bills, and in May, Governor Jay Inslee signed what many described as the country’s most ambitious climate policy package.