Hard to Abate Sectors
We can certainly give up fossil fuels at some point, but 40 percent of all fossil fuel emissions are from hard to abate industrial sectors. Literally, these industrial processes mostly require flames to create oxidation reactions. Electrical resistance heat from renewable energy does not create the flames that create the oxidation reactions. Another 20 percent of all emissions come from agriculture, forestry and other land uses and abuses. These emissions too, are extremely hard to abate. In total, 60 percent of all of humankind’s emissions cannot be eliminated in time frames that matter.
Sustainability of our world, of our natural world from which we humans draw all things, sustainability is paramount. Without sustainability, at some time in our future is in doubt. We will run out, pollute, and over stress so many of our systems that we rely upon that they will collapse.
We as a global culture have made small gains in efficiency of greenhouse gas emissions and renewable energy, but they are still very small, and only a small part of the 40 percent of greenhouse gas emissions that we could possibly eliminate in time frames that matter.
Why are emissions continuing to climb? Fuels Switching, Offshoring, and Renewables
Western nations’ emissions are decreasing, because of fuel switching from coal to less carbon intensive natural gas, from offshoring of goods and services, and from renewable energy. The bottom line with our emissions reductions, is that fuel switching and offshoring of emissions are responsible for over 80 percent of the decline in US emissions.
US Emissions have fallen by 20 percent (about 1,200 million tons CO2) since peaking around the turn of the century, but US offshored emissions have increased by 500 million tons CO2. The shift from coal to natural gas has resulted in a reduction of emissions of another 500 million tons CO2, leaving renewables and other emissions efficiencies at only a reduction of less than 20 percent of the total decline. Part of this small amount of decline from renewables is because natural gas energy production has more than tripled since the turn of the century as the U.S. continues to increase their energy demand.
Renewable energy in the U.S. accounted for 21 percent of total energy generation in 2023, up from 9 percent in 2005. This accounts for 30 percent of US emissions decline since 2005. Fuel switching from coal to much lower carbon intensity natural gas though, is responsible for 65 percent of the emissions decline in the U.S. since 2005; more than twice the decline of renewable energy. This has occurred while energy consumption in the U.S. has increased nearly 50 percent.
Developing nations increased energy demand, and increased energy demand in developed nations are responsible for causing emissions to continue to increase and of course this is only fair. We in developed nations have ours, why should they not have theirs? There is great inequity in assuming that developing nations can reduce their emissions as easily as developed nations. It is relatively easy for developed nations to switch to lower carbon intensive energy sources, but not so in developed nations. To even vaguely approach the energy intensity of developed nations, which is of course the goal to live a higher standard life in developing nations, these nations must not only implement renewable infrastructure, they must implement transmission infrastructure as well. In the US from 2003 to 2023, we easily spent three times as much on energy transmission and distribution infrastructure as we spent on generation.
Emissions Reductions Help, But They Cannot Prevent Our Climate From Passing the Point of No return
Very importantly, there is now a challenging distinction between sustainability behaviors and climate change: Earth’s climate tipping systems have now been activated, like almost every climate impact –generations to a century ahead of schedule.
More than half of known tipping systems are now active when they were not supposed to activate until with business emissions in the latter half of the 21st century or after 2100. These “activations” are deeply tied to Earth systems collapses, like from fire, drought, flood, windstorm, sea ice loss, ice sheet collapse, permafrost collapse, Gulf Stream shutdown, sea level rise, barrier island erosion, coral collapse, etc. Once these collapses begin, like with any collapse, they do not self-restore unless the perturbation (warming or climate change effects) that created the collapse is removed.
About half of these systems collapses have feedback relationship with other Earth systems that increase the speed and extremeness of their collapses. Most of these tipping collapses have activation periods and then what is labelled in findings as “the point of no return,” where the collapse become self-perpetuating even if the perturbation is removed.
The result of these collapses is that right now, Amazon collapse has flipped the Amazon from carbon sink to carbon source with emissions of 1 gigaton greenhouse gases per year. Canadian forest have flipped with emissions of 250 million tons emissions per year and permafrost has flipped with emissions of 2.3 gigatons per year, and as go these subcontinental scale ecologies, likely go similar ecologies globally. These collapses have just begun and have a capacity to increase nonlinearly and far more than they have collapsed so far, enough to dwarf our excess human-caused greenhouse gas emissions. This scenario that is playing out right now, that is unstoppable unless we reduce the amount of carbon in the sky, of which annual emissions are only a small part, will create existential futures for the human civilization without climate restoration.
These collapses can be stabilized, but only if we restore Earth’s climate back to within the evolutionary boundaries of her systems that are now in collapse, and only if this restoration happens before the point of no return. Because the maximum average temperature of our old climate, or the evolutionary boundaries of our Earth systems, was about 1 degree C warming above the late 19th century, to stabilize these collapses we must return Earth’s climate to lower than 1 degree C warming, where we are 1.6 degrees C today.
Fundamentally then, complete future emissions cessation allows activated tipping collapses to complete. Future emissions do matter, but atmospheric carbon removal matters a lot more. Total human emissions since 1850 are about 2,700 gigatons CO2, whereas annual emissions are about 50 Gt CO2.
The fundamental conundrum then is that emissions reductions are not working, and the time it is going to take to remove the excess greenhouse gases from our atmosphere could exceed the time we have remaining until the point of no return. To prevent collapse of our Earth systems with additional natural feedback emissions of greenhouse gases that dwarf humankind’s, we must now cool our climate on an urgent emergency basis through engineered solutions, so that we can buy time to remove excess greenhouse gases from our atmosphere and create a sustainable greenhouse gas emissions future.
