Thanks for adding your voice into the mix here - and welcome to the forum!
I agree that if we are to be alarmist about anything it ought to be climate change. My reticence towards alarmism above was more directed at the dramatic predictions that the public likes to imagine scientists have made that they can then use to poo-poo real science.
It’s just hard to keep warranted alarmism separate (or easily distinguished to the less-than-discerning public eye) from all the “cry wolfism”.
Alan, great to see you here. I’ve learned a lot from you already about this but I have trouble identifying good sources on the internet so I have trouble supporting my suspicions. I think you’ll get better questions here than from those who challenge you at the other site. People here are extremely well informed in their areas of expertise but I’m not sure if we have anyone here studying climate science but I look forward to finding out more.
I’m not sure if there is an information page here about navigating this site but it is so much better than any I’ve used before.
I have read between 50 and 60 books on climate change and associated issues (depending on how you count them), so I could understand the issues in some detail. I summarized a lot of information in another discussion forum as a result. Here are a few points relevant to what I mentioned above:
Some alarmists overstate the disastrous effects of climate change because they don’t understand the part people can play to change what’s happening, or the long time intervals involved. Climate change is a huge but very slow-moving problem. Oceans will likely take centuries to rise. Feedback mechanisms like the melting of permafrost likewise will take time. The problem is that once these effects begin, they will be very difficult to stop. It is best to prevent them from happening at all, which means we need to take action immediately to stay below 2C of total warming. As climate scientist Jerry Mahlman said, “There is no need to exaggerate the problem of climate change; it is bad enough as it is.”
Significant thawing of the permafrost may begin at 1.5C of warming. Nearly a quarter of all the land in the northern hemisphere is underlaid by permafrost. When it warms, frozen organic materials from ages long past will decompose and release their carbon. IPCC climate models likely underestimate warming in this century because they don’t include permafrost releases of CO₂ and methane.
Frozen in the permafrost around the Arctic are an estimated 1.5 trillion tons of carbon, nearly twice as much carbon as in the atmosphere. Most is sequestered in the upper and vulnerable layers, two times more than what is sequestered in all of the earth’s forests. Fossil deposits of CO₂ and methane are already escaping from melting permafrost, and that melting will accelerate as global temperatures rise. By 2100, RCP 2.6 (the low end emission scenario) will result in a reduction of the permafrost by 37%. RCP 8.5 (the business-as-usual scenario) will result in a reduction of 81%. The permafrost could release up to an estimated 275 billion tons of carbon as CO₂ or methane.
Ocean sediments contain around 2 trillion tons of methane hydrates, or methane frozen in water. That’s more than twice the amount of carbon in the earth’s atmosphere. If the oceans warm up enough, such hydrates could slowly melt and release their trapped methane, adding to the greenhouse gas concentrations in the atmosphere. Methane is already leaking out of the shallow east Siberian Sea.
Lakes over permafrost may disappear into the ground, drying out large areas. Permafrost at the bottom of lakes or in wetlands will release carbon as methane rather than CO₂, which will have a much greater short-term impact on the climate. Melting permafrost can potentially release mercury and long-dormant viruses and bacteria as well.
Welcome and thank you for the education! So the question that follows to me is–what is the likelihood and most efficient way of avoiding that amount of warming? It sounds like reiterating what you say assures folks of the truth of the danger and necessity to act.
Competent scientists have worked out the details and the economic involved, but I can respond to your question in general and direct you to the linked website for more details:
Because greenhouse gas emissions are the result of so many diverse human activities, we need to simultaneously change our technologies in multiple areas, including transportation, electricity and heating, industry, land use, agriculture, and waste management. The “wedge strategy” is about bringing down emissions in each of these areas a little to bring down total emissions a lot. Climate change considered as a whole may seem monolithic and intractable, but it can be broken down into smaller, manageable problems. Each solution can make our society work better.
Efficiency measures we can take include improving fuel economy, reducing reliance on cars, building more efficient buildings, reducing production of solid waste, and improving power plant efficiency. Swapping inefficient open fires in developing countries with super-efficient stoves cuts down on black carbon. Decarbonization measures include substituting natural gas for coal, storing carbon captured in power plants, increasing solar and wind energy, and increasing biofuel production. Land management measures include reforestation, reducing deforestation, applying permaculture and no-till agricultural methods, and burying rather than burning solid waste to sequester it. People are working in all of these areas to make significant changes.
All of these strategies are possible, and all will save money and lives in the long run. Our real problem, then, is doing everything we need to do rapidly enough to prevent the potential positive feedback loops from kicking in and making climate change self-sustaining. Time is now a critical factor since collectively we have put off large-scale efforts for so long. Building up nuclear power has price and timing problems. Biofuels have low energy returns on energy invested. Coal with carbon capture is too pricy to be competitive. Solar and wind energy are our best alternatives, but even they have timing problems unless we speed up our transition considerably.
Yet energy transitions are protracted affairs. Climate change has the potential to overwhelm our abilities to cope because it is progressing so rapidly. We can no longer wait for better solutions, but need to quickly transition to the ones we know will work to whatever extent. We can transition yet again to better solutions later, if and when they become available.
Thanks for the clear and concise overview. Beautiful link! Just a bit of background in the 3rd world–I grew up in Niger, West Africa, where deforestation is a huge problem for that very reason. Everyone uses wood to cook; and there are other secondary problems. For example, just as in the Drawdown resource article, many folks in their 50s turn up with emphysema/COPD, from the cooking fires, even though smoking tobacco is not very popular–both from religious reasons and from cost (no one can afford it). My grandpa, who worked for World Vision and then International Aid, tried to work on a jerry can stove (on his own; others had more detailed research) and it just turns out to be really expensive for them to try to change. Many can’t afford even basics like extra cans–poor folks used to come to our house for leftover tin cans to reuse. So, I think that unless the First World can help, the Third World can’t afford to make a great deal of change. However, it will affect them perhaps more quickly than us because of desertification. Here’s a photo of deforestation around Maradi, to the east of us. When I lived there (ending in 1991), there was a herd of 200 elephants reported (I didn’t actually see them because we were several hours to the west). 7 Striking Examples of Deforestation From NASA. I suspect that the herd has shrunk by now.
You might notice that I haven’t really spoken directly to the issue of alarmism. I don’t see how you can exaggerate just how much cause for alarm there is in the problem. The only legitimate objection I can see is simply that we simply do not know enough to be sure about anything. But the answer to this is that we must invest in the research needed to change this.
I see Alan_V largely agreeing with and even underling much of what I have said. The additional information regarding carbon stored in permafrost and ocean sediments, likely to be released by increases in temperature, underlines my statements about the complexity of the problem and the instabilities involved. Furthermore I see significant agreement with regards to the solution being found in science and technology, though his emphasis is more on the reduction of CO2 emissions where I think the focus has to be more on helping and supplementing the conversion of CO2 to O2. To be sure, more of the technology for reducing CO2 emissions is currently within reach and petroleum has too many other uses to just throw it away on fuel anyway. But I frankly don’t think this approach can make a difference fast enough for the climate change problem.
The actual science comes with degrees of certainty, but recently scientists are approaching a very high degree of certainty that human actions are the only significant causes of present climate change. They’ve eliminated all the other possibilities. So that part of the science has already been done.
So my point is that scientists are very certain of the basics at this point, but much less so about other issues, like the rate at which CO2 and methane will be emitted from melting permafrost – which is why they leave them out of their modeled estimates for future warming. Scientists as a whole are conservative, so some of their estimates, like the rate at which ice sheets are melting, have recently had to be revised upwards.
The science is most definitely an on-going process, but we know more than enough to understand we have to take action on a wide variety of fronts. CO2 can be removed from the atmosphere by carbon capture and storage, including by mechanical processes as well as reforestation, but also by changed agricultural processes. Still, that won’t happen fast enough. We will have to reduce emissions as well, which can be accomplished by switching from coal to methane (since methane emits 50% less CO2), by switching from fossil fuels to renewables for electricity, by switching to electric cars (which should be price competitive in the next decade), through energy efficiency measures, conservation, and so on.
Yes I should have been more specific in what I said. I certainly agree that we have a high degree of certainty about the increase of CO2 having a human cause, but considerably less certainty about the direction of climate change. There are too many variables for that. We can measure a 1.4 degree F increase in global temperature since 1880 but do we really know what the temperature change would have been if the CO2 had remained constant? When you look at the extreme changes in temperature in the last million years I see no reason for certainty about the role of human impact on the climate itself.
Switching to renewable sources as much as possible is a sensible long term goal for more reasons than climate change. Switching from one fossil fuel to another is worthy of less enthusiasm and more caution, but it looks like a savings in water usage makes the switch from coal to methane a good idea as well in some areas.
I am not holding out much hope for reforestation. But the plankton is not only the biggest source of conversion of CO2 to O2 but is the foundation of the whole marine biome. A significant drop in plankton is a big problem. But measurements of plankton biomass have been contradictory and that suggests to me that we are missing some part of the picture. Could there be a shift from one strain of plankton to another? We need to find out what is going on with this.
Indeed, on that scale I’m sure scientists don’t bother to express any certainty, as they would know they don’t have it in any case. On those time scales there would be high likelihood that some intervening astronomical or geological upheavals would render all trend predictions null and void. Even on scales of thousands of years I would be surprised if any confidence is expressed [pressed]. That’s why the focus has properly been on a scale of decades and centuries (within our own human generations in other words). Because here, scientific predictions have been seen to be accurate, and so here our concerns should be properly focused and riveted.
While I too have been “guilty” of saying “we need to know more about this” - I’m starting to express or endorse that less and less (except in careful company) because too many latch onto those words and abuse them with deliberate malfeasance to further their own selfish political agenda. [i.e. business as usual.]
Of course we always would benefit from more knowledge and increased understanding. But there is time for action too, and that must always and necessarily come before our knowledge is complete and before our confidence can be certainty. To demand these latter as preconditions to action is to have already taken an action in disregard of the considerable confidence that was already on offer. And as such, I think we can safely label it a damnable cowardice at best, and at worst an evil disregard of all good prudence.
That’s why I hesitate to call all alarmism misguided. Only to the extent that it is used to promote confusion and ultimate inaction do I think it misguided with regard to climate change. But we do need a healthy dose of “wake-up” in multiple fronts. It would seem that many of us here agree about that.
Yep, sounds about right. Wonder if the changes we are seeing in the earth’s magnetic pole is such an event.
I certainly haven’t done that either.
When the actions such as a change to renewable energy sources are a good idea for many reasons other than climate change then I quite agree. That looks like a win win to me.
Scientists have been directly measuring solar irradiance by satellite since the late 1970s, and have seen no changes in solar output except the usual 11-year sunspot cycle, which they compensate for in their climate trend figures. Using solar proxies, they also have a good idea what the solar output was going back much further in time, and understand how it explains some climate changes of the past.
Scientists also know how much warming to expect with every doubling of CO2 (or CO2 equivalent in other greenhouse gases) in the atmosphere. That’s called climate sensitivity, and it is presently considered to be 2.8+/-0.6C (or 5.0+/-1.1F). Any alternative theory for present climate change would have to explain why greenhouse gases wouldn’t produce such warming.
" Researchers at Canada’s Dalhousie University say the global population of phytoplankton has fallen about 40 percent since 1950. That translates to an annual drop of about 1 percent of the average plankton population between 1899 and 2008. The scientists believe that rising sea surface temperatures are to blame."
I should add that although global average surface temperatures have risen on average 1C since 1880, the temperature of the ocean surface water has risen much more, since the ocean absorbs over 90% of the heat from global warming.
“Averaged over Earth’s surface, the 1993–2017 heat-gain rates are 0.36 (±0.06) to 0.40 (±0.18) watts per square meter for 0–700 meters, and 0.19 (±0.07) to 0.35 (±0.03) for depths of 700–2,000 meters. Less than a watt per square meter might seem like a small change, but multiplied by the surface area of the ocean (more than 360 million square kilometers), that translates into an enormous global energy imbalance. It means that while the atmosphere has been spared from the full extent of global warming for now, heat already stored in the ocean will eventually be released, committing Earth to additional warming in the future.”
https://www.climate.gov/news-features/understanding-climate/climate-change-ocean-heat-content
To be thorough in discussing the last million years of climate change, I should also mention the Milankovitch cycles and their effect on ice ages.
In the last 2.7 million years or so, there have been dozens of glacial-interglacial cycles. So the natural pattern of climate change over that period has been one of long ice ages separated by shorter warm periods. It takes tens of thousands of years for the earth to cool down, but only a few thousand to warm again. We are presently living in such a warm period called the Holocene, which started after the last ice age ended around 12,000 years ago.
Scientists are convinced that these natural climate changes can be explained by small shifts in the earth’s orbit, the Milankovitch cycles, which increase or decrease the solar energy it receives. The earth’s axis, the precession of the equinoxes, wobbles on a 23,000 year cycle. The earth’s tilt shifts on a 41,000 year cycle. And the earth’s eccentricity, how elliptical its orbit is, oscillates on a 100,000 year cycle. The 100,000 year cycle has the greatest impact on global average temperatures. Presently, the first two cycles are out-of-phase by about 10,000 years and the orbital eccentricity is small, so the length of our interglacial period would normally be extended beyond the typical. The last time the earth was in this configuration 400,000 years ago, the interglacial was 50,000 years long.
These variations are amplified by the increase or decrease of CO2 which follow them by several hundred years. Soils and oceans release or capture CO2 and methane depending on their temperatures, so both rise and fall in close correlation with the ice age cycles, amplifying their climate extremes. These greenhouse gases account for nearly half the glacial-interglacial global temperature changes. This correlation goes back 650,000 years, through seven glacial cycles.
This is the natural climate change we could expect if no other factors came into play. Nevertheless, present climate change will likely delay the onset of the next ice age for over 130,000 years. CO2 has varied between 180 and 290 ppm for hundreds of thousands of years. It was 280 ppm as late as 1750, before the industrial revolution. But at over 410 ppm today, it is about 45% higher, and likely the highest it has been for millions of years.
RJS had a good blog reproduced here on Scot McKnight’s:
I thought the comments regarding skepticism were quite appropriate.
So owing to these cycles, the earth’s climate does typically rebound between periods of being colder and being warmer. Is there any science to support a theory of what would happen if human activity warmed the planet to the point where the usual cooling cycles didn’t have the usual effects? If we stayed warm while the planet was further from the sun, when we got closer again would we warm up beyond anything the planet would have experienced before as a result of natural disasters? The alarmist picture is the earth becoming another Venus, but of course we aren’t and never will be as close to the sun (well at least until the sun expands). So maybe that isn’t anything to really worry about? But then I wonder just how warm a greenhouse earth could become and how well life could adapt.
I expect that there will be some discussion about appropriate actions, but the primary focus of the remainder of the book will be the development of a biblical and theological case for action. The irony is that we, as Christians, should be at the forefront of a movement to care for others and to act responsibly; yet we tend to be among the most skeptical and least concerned to engage in the issues.
Amen. The disconnect with theology on this issue is rather jarring.
The Earth will never become another Venus, not only because of our distance from the Sun but because our ocean does a lot to sequester carbon over time in carbonate rocks like limestone. That’s not to say that it can’t get a lot warmer, as it has been a lot warmer in Earth’s long history.
The primary reason the Earth has been ice-free for most of its history was because of much greater concentrations of CO2 in the atmosphere. Between 300 and 34 million years ago, there were no large ice sheets anywhere. However, previously large concentrations of CO2 have slowly been reduced, over very long periods of time, by a process called chemical weathering. The uplift of the Himalayan Mountains is considered the cause for the cooling trend over the past tens of millions of years. So the Earth has gradually cooled since 50 million years ago, the ice sheet over Antarctica dates from about 35 million years ago, and the Arctic froze permanently about 3 million years ago.
The chemical weathering of rocks removes CO2 from the atmosphere. This has worked as a thermostat on the earth’s temperature, since weathering increases with more CO2, warmer temperatures, and increased rainfall, and decreases with less CO2, colder temperatures, and decreased rainfall. Plant life also typically acts as a brake on CO2 levels. However, the process of chemical weathering is far too slow to restore the Earth’s natural balance in the short run.
Because natural processes are so slow, we will likely live with whatever climate change we cause for hundreds of years, unless we actively pull CO2 out of the atmosphere and sequester it again.
The main challenge to life is not just the change in temperatures but also the rate of change. The Earth has already seen five major extinction events largely caused by changes of CO2 in the atmosphere much slower than what we are now seeing. That means we could easily see 50% of species committed to extinction before the end of the century with a business-as-usual scenario. The disruption and destruction of the Amazon rainforest and coral reefs, where great numbers of species thrive, make extinctions difficult to avoid. The question then becomes, do we risk badly damaging some key species, like plankton which is at the base of the ocean food cycle?
I’m not sure how warm the Earth could become if we burn all of our fossil fuels, and as a result the permafrost and the ocean hydrates emit their carbon and methane into the atmosphere. But anything above 6C of warming above the preindustrial is typically considered catastrophic. We could be at that global average surface temperature somewhere around 1200 ppm of CO2 in the atmosphere. All the ice sheets would be committed to melting, with the ultimate result of sea level rise of around 250 feet. The Amazon rainforest would be destroyed, as would most ocean life. Most of the western U.S. would become desert, and so on. Again, that’s assuming we weren’t pulling CO2 from the atmosphere and sequestering it, which we would be doing long before then at great expense.
Thanks so much for sharing your knowledge here. We’ve been needing someone with climate science expertise around. In the past, BioLogos has mostly focused on helping Christians come to terms with the science for an ancient earth and evolution, but moving forward they plan to expand their focus a bit, and climate change and environmentalism (we call it “creation care” to make it less scary to Christians) are two areas they plan to delve into more.
Maybe the term “business-as-usual” ought to be eschewed as an impossible option as it is increasingly clear that it isn’t a reachable option even if we politically decided to try going that way. It would be sort of like Indiana legislating that they just want pi to be 3 to make things easier. BAU will be anything but BAU for our children and even (since that doesn’t seem to be concerning enough to capitalistic corporate interests) to us in our own lifetimes and already now if you live in an affected area.
Speaking of large financial powers-that-be, Anand Giridharadas has a critique (described in this Guardian article) for the philanthropic initiatives of billionaires in that so many of them follow the “win-win” mantra. I.e. If a business can make lots of money digging wells in country x or building wind turbines for country y then what’s not to love about that? It’s capitalism finally wedded to green initiative, right? While we certainly shouldn’t turn down any good that is done, what this may really be showcasing is the attitude:
“I won’t be moved to do what’s right unless I can profit from the effort.”
which is also often accompanied by …
“You can ask us to do good deeds - appropriate publicity expected; but you are not permitted to ask us to stop doing the harm that gets us all this money in the first place”.
This may all be pure capitalism and good business, but it should never be confused with good virtue. So Anand is also in favor of retiring “win-win” from our conceptual considerations since we should seek to pursue solutions that are good for everybody [the 90% who really need a win] - even if it hurts the bottom lines of the wealthy and powerful.
Anand’s famous Aspen Institute speech from several years ago is also 30 minutes well-spent where I first encountered his ideas as relayed above.
[Additional thought: Lest this be thought a purely anti-capitalistic screed, I’ll add in an important clarification that I think well-meaning (and especially faith-driven or virtue-driven) capitalists could answer my charge above (that they do nothing if they can’t profit from it) with this response: “Yes, but how much better might an initiative be if it can be self-sustaining rather than depending on continued subsidy?” I.e. No person can keep giving forever at their own expense - their money is finite and must be replenished. And I would respond back: Yes - well and fine; and no doubt (many?) honest business people think along those lines and try to operate sustainably on all fronts including, of course, on their own commercial front. But as long as we see billionaires and near-billionaires accumulating obscene wealth, we all know there is massively more than mere “replenishment” and sustainability going on.]
“Let your conversation be always full of grace, seasoned with salt, so that you may know how to answer everyone.” -Colossians 4:6
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