Care for the Earth
April 30, 2017
Genesis 41:15-24; Genesis 41:27-36
I put on a tie recently and noticed that it was covered in gunk… Looking closer, I made out the image of two hand prints from my grandson Michael’s yogurt covered hands…
Apparently he thought I had tied a napkin around my neck for his personal convenience. I turned to my wife, pointed to the tie, and said “one of your grimy grandchildren’. I’ll come back to little Michael in a moment.
Professor Harvey Weiss has been excavating Tell Leilan in Southern Syria for over a decade now. It was a city that was on the edge of the Akkadian empire from 5000 b.c. until 2200 b.c... It was a city with 3000 years of history that you’ve never heard about. This was the cradle of civilization, the area of the world where we first cultivated wheat and other grains that made possible domestication of animals that led to the development of other technology that eventually produced our first city states.
We have many archeological examples like Tell Leilan. Professor Weiss excavated it, found that it was a small farming village that grew over the next millennia and by 2200 had walls, a developed commercial life, and probably supported 30,000 people. [That made it the Manhattan of the ancient world- huge] Then suddenly, it is abandoned. After 3000 years of occupation, it is abandoned. Why? There is no evidence of war. Was it disease? What was it?
In the past decade, we have developed the ability to analyze soil samples better and in some cases, like that of Tell Leilan, we have determined that the cause was sustained famine. Professor Weiss determined that Tell Leilan had such a sustained drought that all the earthworms died right around 2200. It turns out in the ancient world, the operative number was 5. If you had 5 years of drought, everyone fled and civilization as you knew it there came to an end.
You may know that similar speculation has attended the sudden end of the Maya civilization in South America, and there are half a dozen other examples around the world, several of which I’ve visited.
I suspect that this explains the symbolism of Joseph's interpretation of Pharaoh's dream in Exodus. Pharaoh dreams that there will be 7 years of feast followed by 7 years of famine. He is greatly perturbed. I would assume that, based on bitter history, 7 years of famine means that God (or Nature) is going to wipe everything completely out.
I have to tell you that it is very sobering to stand on these sites, to see all of the intricate stone carvings and the fine temples that adorned these cities. You see how big they are, and it is pretty easy to re-imagine the marketplace open for business and people socializing, children playing in the alley ways. Day turns to week turns to century 3000 years and then they flame out completely.
We don’t have a very good record of seeing catastrophe coming ahead of time and doing something about it in advance to mitigate the social impact. No, we have dozens of examples of civilizations that just disappeared because for a variety of social reasons that died with them, they just weren’t able to change in time.
Vladimir Romanovsky in Fairbanks, Alaska where the permafrost line is in alteration. Romanovsky worked for the Russians when they were building the Gulag on the permafrost in Siberia and he has been studying permafrost ever since. Permafrost, just so you know, is ground that has been permanently frozen for two years or more. There are places in Russia where it runs a mile deep near the Arctic circle and even in Alaska it ranges from a couple hundred feet to a couple thousand. What is happening in Fairbanks is that sections of the permafrost are thawing and when that happens gashes open up in the earth, sometimes rending homes and creating impassable crevasse in neighborhoods.
Romanovsky illustrates his latest findings by comparing measurements of the ground temperature from the lower regions of the permafrost line to the surface. Usually what you find is that the bottom of the permafrost line is the warmest. There is a natural geothermal heat that radiates from the center core of the earth, and the temperatures get steadily colder as you get to the surface. However in the past few decades, he has been getting warmer temperatures on the surface which strongly suggests that the atmosphere is actually generating increasing heat.
Romanovsky explained that this melting may actually contain within it a multiplying effect as the thaw continues, particularly in the active layer, that region of the permafrost that has melted and refrozen annually for thousands of years. The active layer supports rudimentary vegetation such as shrubs, lichen, and some spruce trees. But because the temperatures are so low, when the seasons end, the detritus doesn’t actually decompose but is frozen, and it slowly gets pushed down into the permafrost. If this layer were to permanently thaw, it contains a deep sediment of material that would rot and release methane gas into the air in large quantities.
Methane is a greenhouse gas that is actually more powerful than CO2. This principle of a “multiplying effect” appears to be important in understanding climate change in our world. Because of the complex multiple factors that interact with one another, slight changes here can set in motion a chain of other resident reactions that can accelerate a trend that is already happening.
You probably know that the United States has researchers on the Artic that are being sponsored by the National Science foundation. In 1979, Satellite imaging done by NASA estimated that the size of the Arctic ice mass was roughly the size of the United States. At present, the perennial sea ice has shrunk approximately 250 million acres or an area the size of New York, Georgia, and Texas.
One of the main researchers on the project, Donald Perovich who works for the Cold Regions Research and Engineering Laboratory or CCREL whose area of interest is in solar radiation and sea ice. Professor Perovich uses a device called a spectroradiometer - you don't need to know that I just like saying the name… It reminds me of the movie "Back to the Future" where the eccentric scientist invents a flux capacitor… the spectrodiameter measures incident light (directly coming from the Sun) and reflected light (bouncing back). Dividing the later by the former he factors the albedo (literally the whiteness from Latin).
Hard pack ice is intensely white. As such, the color itself tends to reflect back light keeping temperatures on the surface cooler. Conversely, ocean water is blue, a color that absorbs sunlight and thus heat. The two are nearly opposite of one another. So as the ice melts into water, you are replacing one of the best reflectors of heat with one of the worst reflectors of heat.
Again, there is a compound effect to the system as a whole. As ice spreads, it reflects more and the temperatures on the surface drop adding more ice to the system. Conversely, as ice melts more heat is absorbed by the water which raises the ocean temperature and melts even more ice.
You probably know that the overall temperature of the earth has varied quite a lot in our long history. I was surprised to learn that the majority of the earth's history has had no ice on either pole. However, there has been continuous ice through 4 glaciations that have lasted just over 120,000 years. We do not understand all of the factors as to why we have seen these dramatic shifts in climate, but the principal single factor is thought to be small orbital shifts in the Earth’s rotation around the Sun.
It was in 1859 that the concept of Global Warming was first conceptualized by John Tyndall, the British physicist. He noted that oxygen and nitrogen were transparent to radiation but that carbon dioxide, methane, and water vapor were not. These gases act like an insulating band trapping and storing heat. He, in fact, coined a term we are now quite used to hearing the "Natural Greenhouse Effect". As you know, the principal Greenhouse gas it Carbon Dioxide and Carbon Dioxide is a by-product of burning Coal and Oil, which we have increasingly done since the middle of the 18th century. Carbon Dioxide itself is a "persistent gas”. That means it doesn’t dissipate. Instead, “it lasts for about a century." That means that as it accumulates, it has effects for the future that we will not see for decades to come. The concern about the planet is that forces could be set into motion that will activate resident forces and accelerate a pattern, such that by the time we will actually see the first consequences of these changes, it will already be too late to do anything about it.
As you probably know, we can do some rough measurement of greenhouse gases by studying the ice cores in the poles that have small air pockets trapped that can be analyzed. When you look back over the past 5000 years you see a remarkable consistency in the concentration of greenhouse gases from the beginning of civilization (3500 b.c.) to the 18th century. Then greenhouse gases begin to rise towards the end of the 18th century with the Industrial Revolution.
In 1780 CO2 was approximately 280 parts per million
By 1930 CO2 was approximately 315 parts per million
By 1970's CO2 was up to 330 parts per million
By 1990's CO2 was up to 360 parts per million.
The rise is steeper with more advanced burning of fossil fuels.
It is precisely this steep rise in Carbon dioxide and our responsibility for it that led Paul Crutzen, the Dutch Chemist and Nobel Prize winner, to write an article in Nature a few years ago suggesting a change in the name of the present era. At present, scientists refer to our era since the last glacier as the Holocene era. Crutzen says we should give a new name to the era since 1780 or so as the Anthropocene era, the Human period, because, he argued, humans became the single dominant force that shaped and influenced the total climate of the planet from then on.
As you know, there is no consensus about what happens in the future. We are simply entering unchartered territory and it is far from clear what implications actually follow. In her discussions with climatologists, Ms. Kolbert summarizes a couple areas of concern that they have identified.
One of them is our general findings from the ice cores on the polar caps. One of the things that they make clear is that our present era has been exceptional rather than normative for Earth's history. In the Holocene era, we have been blessed with exceptionally regular weather and exceptionally predictable weather patterns. Over the long term of the Earth's history, dramatic shifts in weather have been the norm and stable weather patterns the exception. Why this has taken place is a matter of speculation, but this paradigm may well be significant for our thinking on the subject of the implications of global warming.
I come back to the notion of complex interacting factors that reinforce and escalate a trend in a direction. One of the scientists that she interviewed used the analogy of a boat. It may be the case that the total systems of the Earth's climate work like tipping a boat. You can tip it and it will swing back, tip it harder and it will swing back harder, but if you tip it beyond a certain point, it flips over. It may well be the case that in the aggregate, when enough resident changes take place, that you have a complete reconfiguration of the total weather system. The study of the ice cores suggest that such a reconfiguration is not only possible but probable.
How would this happen? No one exactly knows. But the scientist Konrad Steffen gives a simple explanation of how weather patterns presently work around Greenland and how they might be altered for the weather over the East Coast.
As you know our Gulf Stream pulls water up from the equator that eventually runs into Greenland and then pushes it down and back south again. As you also know, the weather pattern over the Eastern part of the United States is interdependent with the Gulf Stream.
Professor Stefen explains that there are actually two forces that create the sea lane that is the Gulf Stream. Part of it is what is happening on those major ice masses like Greenland. In the process of salt water freezing, the salt is actually pushed out of the ice towards the exterior of the ice mass. That salt is heavy and it makes the water heavier as it dissolves and this saltier water sinks to the bottom of the ocean. That is one force.
The second is related to the general drift of the warm water to cooler regions. As warm water drifts northward, it cools and evaporates, which means it becomes denser. Again, as it gets towards its northern terminus at Greenland this water too is sinking.
As it does, it creates its own pull on the warmer lighter waters in the Caribbean, so that the overall process resembles a delicate but very powerful conveyor belt of ocean currents.
Now what happens if you add heat to this system? In the first place, the oceans would warm in the south, only slightly, but as they did, this water is lighter and slightly less dense, so it sinks less.
Secondly, if the ice melts then again, only slightly, but you are dumping a large quantity of fresh water into the oceans. They become less salty. They are not as heavy and do not sink as much.
At some point, if these trends continue, it could have the effect of turning down the pump at both ends at once and the sea lanes slow. But as they do, the weather above them also changes. Theoretically, if the sea lanes actually came to a stand still, some people speculate that what would happen is a complete reconfiguration of the weather patterns… That would be something of a tipping of the boat over.
So our cute little story from the Bible might actually speak fairly powerfully and directly to our situation. We keep going along on the same path without actually seeing the ‘signs of the times’ before us and we are quite likely not to see them until it is too late.
And this is one of those rare times when it might not simply be the case that our civilization comes to ill, but my very grandchildren might quiz me late in life, “Papa, why didn’t you do something about this before the seas started to rise and all those poor people that live on the coast were forced to rebuild their lives with precious few resources? Papa, why didn’t your generation think about what they were doing?” Literally, in their life time, the consequences of our collective inaction today will have a material impact on our children’s children.
The earth is a precious and delicate instrument. In former eras, it was understandable that people could think our actions couldn’t have material impact on the environment. The earth, they thought, is just too big.
But now that we are many- the population of the earth has doubled in my lifetime from 3.5 billion to 7.5 billion people… Now that we can measure and compute forward complex models. We have more and more signs in our dreams, with greater specificity than any era of human history. Which makes us more responsible.
And it is personal. We think of stewardship, we all think of providing our immediate families with a better world than the one we had. We all want to take care of these people and that is a large part of why we ‘give back’, we are investing in creating a world of care for them. It is the right thing to do, the loving thing to do.
And I don’t want to answer to these kids questions of incredulity, questions of disappointment. Neither do you. We’ve put this off for too long and now we are about to burden our grandchildren and great grandchildren with our own inattention.
We can do much better than that. The solutions reside inside of us, even as they did for Joseph. Let us pray that we break the cycle of not responding until the end has arrived. Then as now, it is not just about knowledge but about moral purpose too. We may only have an educated guess that we can make, but we need to make one and we need to err in that direction. As Jesus would say, ‘those who have ears, let them hear.’ Amen.