Oceanoxia has a new home! I’ve joined the freethoughtblogs network, and I’m amping up my blog game! Come check it out:
Earth’s systems are already out of balance. The comparative equilibrium we saw during most of the last 10,000 years meant that the amount of ice we had was roughly the amount of ice we were likely to get and keep at our current temperature and greenhouse gas level. When we increased the average temperature, that balance was shifted, and ice started melting in response to the increased temperature of the climate.
The “lull” between 1998 and 2015, which was not much of a lull, still saw accelerating ice melt, permafrost thawing, and sea level rise, because we had already raised the temperature enough to make those inevitable, based on our understanding of physics. Even a year that was down to the 1990 or 1980 temperature level, on average, followed by a return to 2000s temperatures, would have fairly little effect. The melting would have slowed, without stopping, and then sped up again when the temperature returned to the decadal “norm”.
But a dramatically hotter year – like this El Niño year – is a different matter. It injects a bunch more heat into the system, which means faster ice melt, and so lower albedo for the coming year, and more permafrost melt, and so more greenhouse gasses for the coming year, and more water evaporation, and so more greenhouse gasses for the coming year.
A single, unusually cold year, does not do much when we’re still above the temperature at which the current ice sheets formed, but a single hot year can create a spike of warming factors, which will cause even more warming in the years to come.
If we had not been emitting fossil fuels, it’s possible that the dip in global temperatures in the late 1960s/early 1970s would have led to more global cooling, and even an ice age – we’re certainly due for one – but we had already started the slowly accelerating process of global warming. We already had warming momentum, even back then, so we had a temporary cool period, and then when we came out of the 1970s, the temperature skyrocketed.
We’ll have more warming “pauses” in the future. That is a virtual certainty, but unless we re-balance the planet’s temperature budget by reducing greenhouse gases, the planet will just keep warming until it reaches a new equilibrium. Because of feedbacks like the albedo and the melting permafrost, even if we stop emitting CO2 now, the planet will keep warming for thousands of years, and the new equilibrium will be far, far hotter than anything our species has ever encountered.
There are a number of ways we could respond to this, but our best bet is to stop contributing to the problem, prepare for the changes we know are coming, and develop a strategy for deliberately managing the planet’s greenhouse gas levels.
This video is well worth 44 minutes of your time. Dr. Alley knows what he’s talking about, and he lays out the current understanding pretty clearly.
Please educate me if I am wrong, but I have been of the understanding that the Earth has the same amount of water in/on it that it has had for thousands of year, perhaps millions. It is just a matter of distribution. Some zones get way more than they need, and others have droughts.
Sure thing. This will be a bit long, because it’s a complex topic. First off, the only water that counts here is fresh water. Sea water’s not very useful for drinking, irrigation, washing, or industrial purposes.
So we’re focused on fresh water. For the entire history of the United States (and longer for older countries that dig wells) we’ve been relying on subterranian water reserves for a huge portion of our fresh water. Aquifers have a history of having a lot of clean, fresh water.
The first problem is that it takes a long time for them to fill up, and in the last hundred years we’ve been pulling water out faster than they’ve been refilling. That trend has been getting worse as more people have used more water. So those water sources are actually running out – there’s not as much there as there used to be. Once we pull it out of the ground, it becomes part of the water cycle, being moved around as rainstorms, or more often flowing down to the sea. Either way, it was once a reliable source of water, and now it’s not.
The second problem is snowpack. This is part of the drought (water shortage) that California has been facing. Normally large parts of California rely on the snow that accumulates in the mountains during the winter to provide water as it melts. The recent drought has meant that in some places where snowpack – and so water reliability – has been measured, there has been no snow for the first time in recorded history. That means no water. There are a LOT of people around the world that rely on similar patterns of snowfall, and because weather patterns are changing around the world, water availability is too.
And then there’s the question of what makes for “good” water. The reality is that we’ve “removed” a lot of water from the equation by polluting it. Removing some pollutants from water is very, very difficult and expensive, and as with desalination, we don’t currently have the infrastructure to do it at any meaningful scale.
This is why people are so up in arms over hydro-fracking. The waste products of it really are toxic – there’s no question about that, if pour it in the ground, things die. And there’s a real risk that it’s getting in ground water near fracking sites. Once groundwater is poisoned, there is NO method to make it clean again.
Then there’s the issue of changes in temperature. Let’s look at rainforests, for a moment. What’s a rainforest? It’s a place that gets so much rain that water is no longer a limiting resource. Life in rainforests gets so dense and weird and beautiful because there’s just water EVERYWHERE, and so things can grow everywhere. There are temperate rainforests, and there are tropical rainforests. In both cases, the amount of available water is more than local life can use up.
But here’s the thing – tropical rainforests get much, much more rain than temperature rainforests, even though the “saturation” effect is about the same. Why is that? Because tropical rainforests are hotter. The water they get evaporates much, much faster. That means that a place in the tropics that gets the same rain as the Smokey Mountains (one temperature rainforest, at least historically), is NOT a rainforest. It can’t be, because there’s not enough water available.
And that’s the other part. If rainfall stays the same, but temperatures rise, the amount of available water decreases, because more of it evaporates. We’re already seeing the effects of this. In California, before the drought started, we were already seeing some plant species dying out at higher altitudes and repopulating themselves at lower altitudes because while rainfall had stayed steady, temperature had risen, meaning available water had decreased. On the other side of the country in the Appalachians, a decrease in AVAILABLE water and an increase in temperature have meant that some salamander species have been shrinking at a rate of around 1% per generation since the 1980s.
The total quantity of water contained on Earth is much the same as it has been, but that has no meaning if that water is not available for our use, or the use of other life forms.
That’s what is meant by water scarcity.
As I mentioned in a recent post, some form of deliberate management of our climate is an unavoidable necessity. In reality, that’s what all the talk of reducing emissions is about. If we want to be able to control what impact we have on our climate, emissions reduction will not be enough. We’ve already destabilized things, and there is virtually no chance that they will regain stability on their own.
The key to regulating our climate greenhouse gas levels. An increase in CO2 is what caused the warming, and a significant decrease would at the very least slow it. The problem is that even if we were to cut emissions enough that we’re no longer adding to the problem, we don’t have any technology capable of efficiently pulling CO2 out of the atmosphere. Fortunately, we don’t need a high-tech solution.
The solution is trees. There’s nothing revolutionary, controversial, or new about saying this; the tree-hugger stereotype is older than I am. As with the basic thermodynamics behind the current warming, the idea behind planting trees is quite simple. Trees are primarily made of water, drawn from the ground, and carbon dioxide, drawn from the air. As long as you have sufficient water, trees will pull carbon dioxide out of the air, and sequester it in themselves.
This same “equation” is also why the clear-cutting (and often burning) of the world’s rainforests is such a problem – all of that carbon, which had been kept in fairly stable storage by the forests – has been added to the atmosphere along with the emissions from fossil fuel use and livestock. Fortunately, that particular smoke cloud has a silver lining.
If – and only if – the world starts to work together to deal with this problem, the one of the first steps could be replanting as much of the cleared rainforest as possible. This would, of course, have to be done while fossil fuel use was phased out, but a new study has indicated that secondary tropical forests absorb carbon faster than the old-growth forests they would be replacing. In other words – a massive, world-wide replanting effort could create a significant dip in atmospheric CO2 levels, slow the warming, and perhaps even slow or stop the various feedback loops that have already started.
In order to get to the point where we could make this scenario a reality, we would have to overcome the current obstacles of politics and greed, so instead I’ll briefly focus on the obstacle of human necessity. While some of the formerly forested land goes to crops like palm oil, a significant portion also goes to growing food, and by the time we get around to planting on a global scale, the number of humans needing to eat will be even greater than it is today. That means that any effort to replant forests will have to come after an arrangement to ensure food supplies for those currently fed by the farms we’d be planting over.
Dealing with this problem would require a more equitable system of food distribution – one concerned with getting food into mouths, rather than money into pockets (though we can’t ignore the latter entirely), but it will also require new methods of food production. If we want to plant trees where farms exist today, and we want to avoid mass starvation on a scale that wasn’t even possible a few decades ago, then we will not be able to maintain the current conventions of farming, industrial or otherwise.
As the climate continues to warm, weather conditions will become less reliable from year to year. When you combine that with a need for food production to take up less space, and an increasing global population, that points in the direction of multi-story indoor farming. Thus far, it’s a concept that has remained largely in the realm of science fiction or unrealized “concept designs”, but we ought to be taking it more seriously. Moving farming indoors is not romantic, and it feels like a step away from everything we know, but as I’ve said before, we’re effectively living on an alien planet, and maybe it’s time for science fiction solutions.
One of the friendlier aspects of the planet we live on is the very slow speed at which conditions change. Over time, the continents drift about, and new mountain ranges or valleys are formed, and the oceans slosh around in response, but all of that takes far, far longer than the lifetime of any species, let alone any one organism. This means that life has time to adapt to the changes
The climate moves slowly too. When we learn about the ice ages, it seems like a lot happening in not much time. From a geological perspective, that’s true. There have been periods when the climate was relatively stable for many hundreds of thousands of years, but our recent ice ages – the ones our distant ancestors lived through – happened on a cycle lasting tens of thousands of years.
What’s interesting is that while an ice age, or an interglacial period, or a hot period can last for tens to hundreds of thousands or even millions of years, it takes far, far less time to get the climate rolling in a new direction. Huge, slow things tend to build up a lot of momentum, so once they get moving, they’re very hard to stop.
New research from the University of Wisconsin, Madison, looks at the long-term future of our climate, and compares the present with past climate changes. The results indicate something that many of us have long suspected: Even if we were to stop all fossil fuel use today, the planet would continue warming. Not only that, but the effects of what we’ve already done are likely to last 10,000 years or more.
I came to the realization some years ago that climate change was something I would be involved in for the rest of my life, but the reality is that it’s something that every organism on this planet will be involved in. This issue will not go away in our lifetimes, or our grandchildren’s lifetimes, or their great-grandchildren’s lifetimes. While we may have had an opportunity to prevent this future, that opportunity has been lost, barring some form of atmospheric carbon capture that works faster than the rate of increase from human activity, and from the numerous feedback loops that are already in action.
Of course, we can always make the problem worse – continued fossil fuel use, continued deforestation, and continued reckless farming methods could result in a much faster rise in temperature that would last much longer. There is no scenario in which it cannot get worse, up to the point where there’s no life left on the planet, so there will never be a point at which “we might as well give up” will be a legitimate argument.
But it is no longer enough to focus on reducing emissions. In reality, that hasn’t been enough for at least a decade. We need to reduce emissions, but we also need to prepare, if we want civilization to survive. We need to plan for a future in which the seas will not stop rising – not for hundreds, or thousands of years. We need to plan for a future in which farming conditions will never be reliable year to year, or decade to decade. We need to plan for a future in which diseases are no longer limited by the climates of different geographic regions.
Like it or not, we now live on an alien planet. It seems similar to the one that gave rise to our civilization, but it isn’t the same, and it will keep getting more different with the passage of time. The longer we avoid coming to terms with that fact, the more will be added to a death toll that is already climbing due to our actions.
It isn’t fair. Nobody in my generation chose this. A majority of “boomers” didn’t either. Not any more than they chose to be exposed to leaded gasoline or chose to be expose to cigarette smoke. And as much as I feel that I’ve been handed a problem that should have been solved before I was born, I’m one of the lucky ones. My country will do OK, overall. Provided we don’t start a nuclear war or something like that, we’ll do far, far better than the billions whose countries had no real role in creating this disaster, and the billions more who will be born too late to even remember when people were trying to prevent it.
I think that, as a species, we can weather this storm of our own making. I believe that we can, in coping with these changes, build a more resilient and just global society, and have a healthier relationship with the rest of life on Earth. We’ll have to, if we’re going to avoid extinction.
Like all those who have created or consumed post-apocalyptic entertainment, I can see many paths to a desolate future. I can also see many other futures, and they’re worth working towards. As a species, we have the power to build a future in which we surmount the obstacles placed before us by our elders, and to keep climbing to something better. There’s no easy path anymore – the easy path would have been to avoid this in the first place. But I can see futures worth working towards, and I think we need that right now.
Over the last couple decades, the world’s business and political leaders have gradually come to understand that climate change is something that cannot be ignored. Every year, the immediacy and severity of the problem have become clearer. Sea level rise, seasonal changes, and even evolutionary changes in response to the rise in planetary temperature have all made it clear that the entire planet is changing around us, and that ignoring it could have devastating results.
Living, as we do, in a society that values money so highly, some of the responses have been predictable. In particular, businesspeople like Bill Gates have been pushing
the idea of geoengineering as a solution. Geoengineering, in this context, is a catch-all phrase for deliberately tinkering with Earth’s climate and the mechanisms that affect it. The problem with this is that the term is so broad it’s almost useless. It can apply to things like planting more trees, and it can also apply to colossal structures in space to reduce incoming sunlight.
One of the most commonly discussed geoengineering solutions is iron fertilization of the ocean. The basic idea is simple – iron is a limiting nutrient in the ocean, so putting iron particles in the ocean will stimulate the growth of photosynthetic plankton, which will pull CO2 out of the atmosphere. The idea is that when the plankton die, a sizable amount of their mass will sink to the bottom of the ocean taking that carbon with it.
It’s not really clear how well this works in practice. Some studies have indicated that it would work, while others indicate that it might not have much effect, and some people have raised concerns that it might actually result in eutrophication and dead zones.
Newly published research now indicates that because iron is not the only low-availability nutrient in the ocean, the algal bloom from iron fertilization in one part of the ocean might pull other nutrients, like nitrates and phosphates, out of the water, starving plankton farther downstream along the oceanic currents.
It’s tempting to simply wave away geoengineering as a bad idea that we should bury and be done with. There are countless ways that it could go horribly wrong, especially when enacted by billionaires like Gates and his ilk, who have little to no understanding of the ecosystems with which they want to tamper. With the possible exception of planting more trees and creating more wild spaces (which would, without question, work), pretty much every proposal for geoengineering has the potential to have devastating side effects that could make life on Earth much more difficult.
There’s one compelling reason not to throw it away altogether. The reality is that we are already engaged in geoengineering, and there is no question that the path we’re currently on will end badly. Like it or not, humanity has become a force of nature. The size of our population and the scale of our technology mean that we exert a global influence of the chemical makeup of our planet’s oceans, atmosphere, land masses. Currently, we are engaged in the kind of geoengineering that Svante Arrhenius calculated was possible over a century ago – raising the planet’s temperature by increasing greenhouse gas concentrations.
For the sake of our own long-term survival, not to mention the rest of life on Earth, we need to come to terms with the fact that our species exerts a global influence, and we need to take deliberate control of that influence. We are already geoengineers, we’re just not taking responsibility for it. It’s past time to do more than simply work on reducing our fossil fuel use – we need to think about how we manage the surface of the planet we live on, and how we can manage it for the benefit of all life on Earth – ourselves included.
Because right now, we still seem to be pretending that we can just stop having a planetary impact, and with our population headed for 10 billion in just a couple decades, that is the one option that is no longer available to us.
A couple days ago, scientists at the University of Texas at Austin’s Institute for Geophysics published the first map of Greenland ice movement over time, and compared the current rates of ice movement to the historical trend.
Their basic finding is that the current rate of Greenland ice movement is slower than the average rate of the last 9,000 years. This is basically due to differences in Earth’s atmosphere over time:
During the last glacial period, higher rates of atmospheric dust deposition produced softer ice, which flowed more readily than cleaner ice. During most of the Holocene, though, atmospheric dust concentrations were lower, and the less-dusty ice that formed was stiffer, meaning it did not flow or thin so rapidly. Thus, the thickening seen today in the central regions of Greenland is partly a response to changes in ice rheology that occurred thousands of years ago.
Presumably this dust disparity doesn’t include the late 19th century leading into the 20th and 21st centuries.
This research – like a lot of climate research – can be a bit confusing to non-scientists. If you’ve paid attention to what sundry news sources have had to say about climate change and Greenland ice, you’ve probably gotten the impression that it’s not only melting, it’s also sliding into the ocean faster every year. That’s the impression I had, and it’s the impression the authors of this research had too:
“Like many others, I had in mind the ongoing dramatic retreat and speedup along the edges of the ice sheet, so I’d assumed that the interior was faster now too. But it wasn’t,”
Based on my experience in climate science communication, at some point the community of climate deniers will seize on this (with glee) as “part of a growing collection of evidence that things aren’t actually as the ‘warmists’ would have us believe”. And, to be honest, most advocates for climate action will probably ignore these findings, for the most part, because at first glance it seems like the deniers might have a point.
The problem is that we’re really good at taking “first glances” and really bad at getting the right impression from them, and as with much of science, this merits deeper discussion.
First of all, while the interior of Greenland is moving more slowly than it used to, the outer edges are moving much, much more quickly than they used to, and contributing to sea level rise. It is expected that as the edges of the Greenland ice sheet crumble into the ocean, and as temperatures continue to rise, the interior of the Greenland ice sheet will probably speed up again.
And that brings us to the second point. People of all stripes have a tendency to focus on research that supports the views they already hold, while discounting or ignoring anything that might challenge their beliefs. While they are not alone in doing this, the climate denial movement is particularly adept at it. They will take isolated bits and pieces, behave as though those bits and pieces are all of climate science.
The reality is that as long as greenhouse gas levels continue to rise, the planet’s temperature will also rise. That’s basic thermodynamics. If you increase the insulation around something, without reducing the amount of incoming heat, then it would be physically impossible for it not to warm.
The Earth’s temperature will continue to rise (and that includes both ocean and atmospheric temperatures) because we are continuing to add greenhouse gasses to the climate system. The rise in temperature has already led to rising sea levels and melting ice around the world, including Greenland. Higher temperatures will mean more melting. Again, that’s basic thermodynamics. This research shows that the changes in temperature and greenhouse gasses are not the only factors at work, and that’s good to know; but in the end, these data do not call the laws of thermodynamics into question.
There’s one more thing to mention about the deniers. A large part of their “case” rests on the notion that the scientific establishment is, in fact, suppressing or ignoring any evidence that might challenge the mainstream understanding of Earth’s climate. It’s a seductive message (there’s a reason there are so many conspiracy theorists out there), but one that is without merit. This is a clear example of a scientist going into his research with an expected finding (he thought he’d find accelerating ice movement), getting a result that was the opposite of what he expected, and reporting on it anyway, because for a majority of scientists, that’s just what you do.
Dishonesty is a factor in all human endeavors, and there are many examples of scientists fudging the numbers. It is important to note, however, that those lies are found out, usually by scientists, and that over time the record is corrected. The field of climate science is almost 200 years old, and for a majority of that time, we’ve known the thermal properties of CO2 and other greenhouse gases. We’ve also known that increasing those gases will cause Earth’s temperature to rise. Unless someone manages to produce and support research that undermines those basic facts, there is NO reason to think that Earth’s temperature will do anything other than rise, and keep on rising as long as our greenhouse gas emissions maintain a themal imbalance.
I’ll let Pippa get the last word on this –
In a country that has, for many years, been at the forefront of scientific innovation and technological development, everybody (excepting a few religious fundamentalists) claims to value science, and yet we consistently see policies and behaviors that seem to ignore reality.
So what does it mean to value science? Is it like the lip-service version of “valuing life” that goes along with building the world’s most deadly military? Do we value it at a distance, in a sort of abstract manner?
For my part, I feel that if we value science, then we need to consider how its findings connect to other things we value. Take the current example of Flint, MI. We have known that lead is dangerous for thousands of years, and more recently had a refresher of that lesson with the rise and fall of tetraethyl lead. We know that the Flint River is more corrosive to lead than the lake water coming from Detroit. We also know how to treat water so that it won’t corrode the lead in pipes.
At a minimum, valuing science should mean accepting its findings, and acknowledging what we know about reality, but what then?
Then we get to other values. Most people claim to value human life and wellbeing, so it should be a simple conclusion – either avoid water sources with a low pH, or treat the water to protect the population from lead poisoning. Supposedly, Governor Snyder and his “Emergency Financial Manager” made the choices they did because they value fiscal responsibility.
Before we address the financial aspect of this, let’s dwell on the implications here for a moment. The decision to change water sources and the decision to not treat the water were made in order to save money, and that goal was more important than the wellbeing of the people who would be using the water. That is the best possible explanation. That means that to the people making those decisions, human life and wellbeing is worth less than whatever money they thought they could save.
But let’s set aside, for the moment, the moral outrage of valuing the lives of our fellow humans so little, and consider the supposed reasoning behind this disaster. The idea was to save money. With the information available BEFORE the change was made (years, decades, and in some cases centuries before), no responsible financial calculation could have left out the impacts of widespread lead contamination in Flint.
If life was valued, then they would have taken care to treat the water or not make the switch if they couldn’t afford the treatment.
If fiscal responsibility was valued, then again, treatment or not switching were the best options, given the short-term and long-term costs associated with untreated water.
If science was valued, then that value did not extend beyond mere academic interest, and into any kind of informed action. In that case, I think that were Snyder to claim to value life, fiscal responsibility, or science, he would be demonstrating only that he does not value truth.
In the absence of any honest statement of the values that went into creating this human rights disaster, we are left wondering what was really at work. Whether it was the manifestation of a belief that government is inherently evil (surely a self-fulfilling prophecy from someone with power over government policy), or a desire to transfer wealth (financial or otherwise) from the hands of poor, black folks to the hands of rich, white folks, or any of the other motives suggested, this does not seem like an isolated incident.
The poisoning of Flint, MI parallels many, many other cases of environmental contamination, including the destabilization of Earth’s climate through fossil fuel use. It seems that the values that have lead to decades of obfuscation and inaction surrounding climate science, are the same as the values behind disasters in Flint, the Gulf of Mexico, Los Angeles, Bhopal, and countless other places around the world.
I don’t have a solution, but I think it’s important to state as clearly and as often as possible that the ideological movements behind all these crimes against humanity and against life on this planet are tied together. Without identifying and solving that problem – as well as our own participation and contribution to that ideology – it seems unlikely that we will be able to fix the crises before us, or prevent the new ones that loom on the horizon.
Note: This post is relevant
A recent report has garnered some attention for its declaration that we have entered Earth’s sixth Mass Extinction – the first since the disappearance of the dinosaurs. They also state that humans, as a species are at risk of going extinct.
I’ve got lots to say about all this, but right now I want to address how we know what we know.
Most people not involved in the study of plant and animal populations don’t have a very clear idea of how scientists come to conclusions like this. There’s no reason they SHOULD, but having an idea of how we know what we know can act as a defense against those who say things like this are all made up.
When I was in college, I spent one week on some islands in the Bahamas (terrible, I know), studying a population of iguanas. I was part of a group of around 10 people led by a biologist who had been doing this for 20 years. This species only lives on three islands, and was almost extinct when he started studying them.
20 years later, with the help of the Bahamian government, they were doing quite well, and he had a massive amount of information about the iguanas, how long they lived, how many there were, what their breeding habits were, and so on.
This was achieved by spending between two weeks and a month on the islands about once a year.
This same biologist was doing similar studies of turtles in a couple places in Indiana, Nebraska, and probably a couple other places I’m not remembering.
I also spent time in Tanzania, and talked to biologists there who were studying everything from plants to elephants.
I also talked to scientists at the New England Aquarium that monitor fish and sea turtles populations all along the East Coast of the United States.
When I worked for a state department of natural resources, I spent two summers doing similar work to what I had done with the iguanas and turtles, this time with snakes. There were fewer of us studying many more populations, so it took us a full summer to cover about half the significant habitats in the state.
I also did some filing work for that department, going through the records of citizens reporting in about animals they had seen.
Now I regularly interact with people who are doing the same thing with bird species – counting them, weighing them, and monitoring how their populations have been changing for the last 50 years.
I’ve also been talking to people who’ve collected plant and bird records from scientists and hobbyists going back in to the 1800s.
This is just the tangential experience of one person, who studied biology as an undergrad in one college, and worked for a couple science-related organizations afterwards.
In the U.S. alone, there are thousands of colleges and universities that do similar kinds of research at different levels. Every state has an agency that ALSO hires scientists to do research. Every state also has people who closely monitor wildlife for their own reasons – hunters, birdwatchers, reptile enthusiasts, frog enthusiasts, fishermen, and so on.
Many of the colleges I mentioned ALSO do research in other countries all over the world, but all of those countries also have their own researchers and institutions doing their own work.
This work involves individually counting lizards, or snakes, or turtles, or birds, insects, or fish, or mammals, or plants, or sometimes number of flowers ON plants.
On every continent, in every country, in every habitat in all conditions of all seasons, there are thousands of people constantly monitoring the myriad of organisms we share our planet with – and in some cases rely on.
All of these people also share their data, and publish it, and cross-check it, and add it in to common databases that cross international boundaries. All of this work goes back generations, and as the human population has grown, so to has the number of people studying the world we live in, as well as our capacity to do so.
That is how we know that species are going extinct. That is how we know that the climate is changing – because for every person I mentioned who’s studying life on earth, there’s also someone studying the planet’s past, and someone studying the chemical composition of the atmosphere, and someone studying how those chemicals behave in different conditions.
The entire planet is changing all around us, and everybody who’s watching can see it.