The Abomination of Speed Humps

Speed limits in the United States are set by each state or territory. In Texas (where I live), the default state speed limit inside a city or town is 30 miles per hour for a normal street and 25 miles per hour in an alleyway. Thus, if you are driving on a normal street, you should assume that the limit is 30 miles per hour, unless you see a sign posted with a speed limit to the contrary,

Many neighborhoods in Texas have been obstructing the Texas state law, in my view, by installing so-called speed humps on various streets. These speed humps are intended to force people to slow down to speeds of 5-15 miles per hour, depending on the vehicle, or else incur damage to their vehicle (for example, a busted oil pan), or, even worse, have an accident.

States generally allow a statewide transportation agency and lesser authorities to change speed limits, as does Texas. I have a brother-in-law who lives in a neighborhood in a small town about an hour north of Houston. He strongly objected to folks driving through a particular intersection at speeds more than 20 mph. Did he lobby to have speed humps installed? No, he did not. Rather, he talked to his neighbors, and they went through the proper procedures to get the law changed. Now, there is a 20 mph speed limit sign posted at the intersection, with warnings about heavy fines should you ignore it. It worked.

I abhor speed humps. My opinion is that if you want people not to drive more than 20 miles per hour on some street (or 15 miles per hour, or whatever), you should get the speed limit changed and get signs posted to that effect, just like my brother-in-law did. If instead, you get speed humps installed without changing the limit, not only are you thwarting the normal legislative process, but also you are misleading drivers, basically saying to them, “The speed limit is 30 miles per hour, but (Psyche!) it’s really not, because if you actually drive at that perfectly legal rate of speed, you may damage your car and possibly even have an accident.” This is insane, and it is wrong, wrong, wrong!

I detest speed humps for three reasons. First, and mainly, they are a de facto obstruction of state law. Second, they can have bad unintended consequences; for example, accidents can happen if drivers ignore the speed humps and drive the legal limits on these roads. Third, they are routinely misrepresented – people are generally told that they should slow down to 15 miles per hour, when in fact, they often must slow down much more than this – in my car, you had better not go more than 5 miles per hour over them or you’re asking for trouble. The first time I encountered a speed hump, I slowed down to only 15 miles per hour and damn near had a wreck. Incidentally, they are also named wrong – they should be called slow-down humps, or something like that; I guess that makes four reasons, doesn’t it?

There Are Heroes and There Are Heroes

This past Tuesday afternoon (July 27, 2010), I boarded a 45-minute flight in Cincinnati, Ohio, bound for Columbus, Ohio. It was one of those wretched little Embraer jets with one seat on the left side and two on the right. I wound up sitting next to this old man on the two-seat side. After we were in the air he mentioned something about the tight quarters and said he had just had to turn down a trip to Korea because he didn’t think his legs would take the punishment. Said the trip would have been paid for, but he just had to turn it down this time; and, after all he’d been there something like twelve times already. I asked him what the trip was for, and learned it was to receive some kind of award or honor.

He said he had traveled all over the world, but now at 81 years old he was having to slow down. Somewhere along in here he mentioned that he had known every President since [Franklin] Roosevelt. Said he had been to 13 of the 14 last inaugural balls; seems he couldn’t make it to Eisenhower’s first one because he couldn’t afford to buy his wife a new dress at the time. He told me quietly that you couldn’t take your wife to an inaugural ball in a gingham dress. I asked him if he knew President Obama, and he said yes, that he had walked with him in a ceremony a year or so ago and placed a wreath at the Tomb of the Unknown Soldier. Seems he knew General Petraeus and General Tommy Franks. Eventually, he showed me two photos in his wallet. One was him standing with President Truman, and the other was him standing with President Kennedy. He said Kennedy once invited him to a cocktail party, and that he had ridden with him on Air Force One.

I asked him what he was so famous and well known for, and he just leaned over and showed me his coat lapel, on which was sewn a patch saying he was a Medal of Honor recipient. After a little while, he told me an amazing story about a battle in Korea that he was in (apparently the one that got him the Medal of Honor). Once he mentioned vaguely that he supposed he was naturally good in combat (so it would seem!). He said he had been wounded several times (four Purple Hearts I think he said). He told me that there were plaques and portraits, etc., honoring him at various places around the country, naming a city or two as he talked. For example, there was something about him in the Ohio State House. He travels here and there, raising money for wounded war veterans and so on. Just as we were getting off the plane, I asked him his name, which was Ronald Rosser. When I got home, I searched for him on Google, and lo’ and behold, there he was in Wikipedia.

Subject: Ronald E. Rosser - Wikipedia, the free encyclopedia

http://en.wikipedia.org/wiki/Ronald_E._Rosser

But I couldn’t really be sure that the man on the plane was, in fact, the same man as the Ronald Rosser who was written about in Wikipedia, because the photo there was of a relatively young soldier, and the man on the airplane was 81. However, the description of the battle in Wikipedia was remarkably close to the description he gave me on the plane, so I kept looking until I found a newspaper story containing a recent photo, and Bingo! It was definitely the same guy.

Subject: The Daily Nightly - Medal of Honor: Ronald E. Rosser

http://dailynightly.msnbc.msn.com/_news/2007/09/18/4373633-medal-of-honor-ronald-e-rosser

Nowadays, you might be called a hero if you rescued a cat from a tree, but not so much back in the 1950’s, and I knew I had been sitting next to a genuine American hero of the first water.

Blow the Well Up

Okay, who besides me thinks it's time for the United States Marines to shove BP the hell out of the way, and blow the Macondo well up? BP keeps screwing around trying to put a dome over it, and trying to draw oil off through a straw, and shooting junk into it, etc., failing again and again, while meantime the Gulf coast is being destroyed. Oysters, shrimp, fish, birds, beaches, marshes, and many people's livelihoods and ways of life are being destroyed. Blow-the-well-up technology has been around since at least as early as the 1960's, and many oil well blowouts have been stopped by blowing them up. But if BP did that, it would lose the investment it has made in the well and all the potential future revenue from the well's production. BP estimates that the oil seam holds 50 million barrels. Consider that 50 million barrels of oil at $50 a barrel is 2.5 trillion dollars. Blow the well up, for God’s sake.

Black and Brown

When I was 35 to 37, I worked in Washington, D.C. in an unusual job. I was expected to make relationships with certain people in the Executive branch of the federal government; i.e., the DOE, the EPA, the DOS, etc. I was charged with spreading the good word on natural gas to the people who made the regulations to enforce the laws that Congress made. The higher the person was in the government hierarchy, the better. When I got there in 1979, the Natural Gas Policy Act of 1978 had recently been passed. This was the first federal natural gas act in forty years, and it fundamentally changed the way the natural gas industry worked in the United States.

At the time, El Paso Natural Gas Company was my employer, but they had selected me to work on loan assignment for the American Gas Association in a unique group of five or six other people, all of whom had been selected by their respective employers like I was. The group composition changed on occasion, because the members would join it maybe at different times and stay there one or two years (in my case, three). The members of the AGA were all gas pipeline companies and local gas distribution companies. Also, only AGA members could potentially nominate a person to serve in the group I was in. Consequently, all of us in the group knew something about the natural gas industry.

While in Washington, we worked in generally different areas. For example, Michelle might target the Department of Education, the CSPC, the Department of Health, and maybe a couple of other agencies, whereas Don or Geoff might aim at the Department of Interior, the FERC, the FCC, and the NTSB. I worked at getting to know the people at the Department of State and the Department of Commerce, the DOE and the EPA, the Pentagon, and the MSHA. The “boss” of our group was actually more of an advisor. He was a retired Colonel named Dallas, and he knew a lot about how the government worked. A great guy, but that’s another story.

It was a fun job, and everyone in the group felt important. We all got along great with each other. The full-time employees far outnumbered our small group, but we worked right along with them. The AGA has full-time Congressional lobbyists working for it, as well as people that analyze gas policy, gas economics, pending legislation that might affect the gas industry.

For about a year I had been trying to get an appointment with the head of the Mine Safety and Health Administration. I finally got one, and on that day, I really cleaned up. I got up early, and showered, shampooed, shaved real close, brushed my teeth extra well, combed my hair special, and got dressed in my best three-piece suit. When I got there for the appointment, I was led to a nice sitting-room, with a sofa and upholstered chairs, and a large glass coffee table. My adrenalin was spiking. I was going to knock the socks off this guy with my spiel on the natural gas industry. When the MSHA director came in, we sat down at his coffee table. His assistant served us something to drink, and we exchanged small talk for a few minutes. When it seemed like the right time, I reached down to get my briefcase with all the stuff I was going to show him.

And that was when I discovered that I had put on one black shoe and one brown shoe.

Fire at the Filling Station

Static electricity can be a source of ignition. Static ignition has started fires involving people filling their vehicle tanks with gasoline. Static charge buildup is generated when liquids move in contact with other materials, such as when gasoline flows through a hose and nozzle. The vehicle in this photograph experienced a fire caused by static ignition.

Vehicle service station pumps usually have warning signs posted about the danger of static ignition. The signs have instructions on how to reduce the chance of it happening. The gasoline nozzles also have warnings that can be read while you are filling the tank. One warning says to keep your hand on the nozzle while filling the tank. Do not set the nozzle on automatic fill and leave it to go get something out of the car, or to go into the store, or whatever.

This is because while you are sliding across the car seat or walking around, you can build up a static charge that is different from the one that is building up on the nozzle. Then, when you return to the nozzle and touch it, if the difference between the static charge on the nozzle and the one on you is great enough, a static discharge will occur. This creates an electric arc between your hand and the nozzle. If the electric arc has enough energy, and if other conditions are right, the gasoline fumes will ignite.

Also, if you are filling a portable gasoline can, place it on the ground first. If you fill the can without first removing it from your truck bed or car trunk and placing it on the ground, you are courting the possibility of static ignition.

This is a photograph of a warning on a gasoline pump at a service station near my home.

This is a photograph of the warning on the gasoline nozzle:

I Like Ockham's Razor

Ockham’s Razor is a principle espoused by William of Ockham in the fifteenth century that translates as "entities should not be multiplied unnecessarily". In other words, if you have two theories that are both consistent with the observed facts, then you should use the simplest theory, unless and until evidence to the contrary is revealed.

For any given set of facts there are an infinite number of theories that could explain them. For example, if you have a graph with four points in a line, then the simplest theory that explains them is a linear relationship. You could draw an infinite number of different curves that all pass through the four points, and there is no proof that a straight line is the right one. However, it is the simplest possible solution. Therefore, you might as well use it until someone comes along with a point that is not on the line.

The Day the Slop Oil Tank Blew Up

I’ll bet there have been times when you heard about some big explosion at a refinery or chemical plant or whatever, and you wondered what the cause was. Or you’ve heard some TV announcer say something like, “Investigators at the scene are trying to determine the cause…” But have you ever considered the possibility that it might have resulted from a chain of events, not just one, and that if even one of those events had not occurred, the explosion would not have happened?

Well, I have. I learned a long time ago that explosions sometimes happen exactly like that. The ones I’m going to tell you about occurred several years ago. A refinery slop oil tank blew up, releasing boiling hydrocarbon liquid and volatile gases. They formed a huge explosive cloud that exploded several minutes later

Refineries have slop oil from spills, off-test products and whatnot. It is captured in the wastewater treatment unit by a separator that operates on the simple principle that oil floats on water. The oil is decanted off from the separator and heated to 250-300 degrees Fahrenheit to lower its viscosity, making it easier to pump. They pump it to a slop oil tank, and from there they feed it back into the refining process.

You might be wondering why a slop oil tank would blow up. I mean, it’s an uncommon thing to happen. You might be wondering why boiling liquid was involved. You might even begin to suspect that something other than slop oil was in the tank. You would be right. It turns out that the refinery was using the slop oil tanks temporarily to store highly volatile hydrocarbon liquids produced by the cat cracker.

The catalytic cracking unit is a major processing plant in an oil refinery. It is commonly referred to as the cat cracker, or the cat unit. It breaks up long-chain petroleum molecules and converts them into propane, butane, and a variety of intermediate liquid products used to make gasoline, jet fuel, and heating oil.

Propylene and butylene are cat unit products. These compounds are called olefins (which is merely a generic label for organic compounds with one or more double carbon-carbon bonds). Typically, these particular olefins are used as feedstock for the alkylation unit. The “alky” plant, as it is typically called, chemically combines the olefins with butane to make iso-octane, which is a key component of gasoline.

The alky plant at this refinery used hydrofluoric acid as a catalyst. (Some alky plants use sulfuric acid.) For a couple of days prior to the explosions, the acid pump seals kept failing and shutting the plant down. The acid was disintegrating the pump seals and spewing out all over the place.

Now think about what’s going on here – the pump seals fail, and the plant shuts down. They replace the seals with the same type, and start up the plant again. The seals fail again, and the plant shuts down again. They replace the seals again with the same type, and start up the plant again. And they do this repeatedly, apparently expecting different results each time they do it. Duh?

Well, surprise -- it later turned out that the seals were no good for acid service. Someone purchased the wrong type. This could have been a purchasing error. Or it could have been that these seals were cheaper than the right kind. Anyway, this was the first event in the chain. The second was when the people installing the seals did not catch the error.

With the alky plant out of commission, there was no place to put the cat unit olefins. The refinery manager was not about to shut down the cat unit. Instead, he decided to put the olefins into railroad tank cars. This worked out kind of okay until he ran out of tank cars. Then he decided to pump out the slop oil tanks, and put the olefins there for the time being. He also had a written order entered into the wastewater treatment plant manager’s log, saying not to pump any slop oil to the slop oil tanks until further notice.

Now, slop oil tanks are vented to the atmosphere. At atmospheric pressure, propylene and butylene boil at temperatures well below zero degrees Fahrenheit. Consequently, the olefins in the slop oil tanks were boiling, and the vapors were being vented. Moisture in the air froze on the outer surface of the tanks below the liquid level. Ice coated the exterior surface of the tank from the ground to the liquid level.

Meanwhile, down at the wastewater treatment plant, things were getting dicey. Slop oil piling up in the separator would soon start overflowing into the river. The plant manager wasn’t about to get fired for letting that happen and getting hit with huge cleanup costs and EPA fines for killing the fish, not to mention for losing product. So, he ordered one of his men to drive over to the tank farm and look at the ice on the slop oil tanks to see if there was any space left in either of them (there were two slop oil tanks).

Take note here, that the wastewater treatment plant manager has no clue as to what might happen if he pumps 250-300 degree slop oil in with the olefins. He knows the ice forms on the tank because the olefins in it are boiling, but he doesn’t equate that knowledge with anything other than how full the tanks are. He’s thinking only in terms of how much room there might be left in the tanks.

Anyway, when the wastewater treatment man got to the slop oil tanks, he radioed back to his plant manager that there was about four feet of room still left in the top of one of them. So, the wastewater treatment plant manager – with complete disregard for the refinery manager’s written order – started pumping the hot slop oil to the slop oil tanks at about 200 gallons per minute.

Now, any given volume of propylene expands approximately 300 times when it boils into gas at atmospheric pressure, and butylene expands about 200 times. When the hot slop oil reached the tank, it quickly vaporized huge amounts of the olefins. The tank vents were woefully undersized to accommodate the enormous volume of gas suddenly being created inside the tank. The vents were designed to handle normal tank “breathing,” not something like this. The resulting sudden overpressure blew the roof off, releasing an enormous volume of boiling hydrocarbon liquid and volatile gases.

You probably know that the range of concentrations of hydrocarbon gases in air that form an explosive mixture is typically fairly narrow. For example, gasoline vapor will not ignite unless there is at least about 1.4% gasoline vapor in air. On the high end, gasoline vapor will not ignite if there is more than about 7.6% gasoline vapor in air. So, the “explosive envelope” for gasoline is about 1.4-7.6% in air. Corresponding values for propylene are 2.0% and 11.1%.

Thus, for the gas to be explosive, it must be diluted tenfold or more with air. To put this into perspective, suppose that one cubic foot of liquid propylene forms 300 cubic feet of propylene gas. This is diluted with air to form between 2,700 and 15,000 cubic feet of explosive gas-air mixture, depending on the dilution factor (300/0.111 = 2,727, and 300/0.02 = 15.000).

So, the olefin vapor cloud floated out over the refinery, with air diluting it as it went. By the time the cloud contained enough air to make it explosive, it was enormous, and it was searching for a competent source of ignition. It found it about 300 yards away, where three men were working with welding equipment, and a tremendous explosion occurred.

All four men died -- the wastewater treatment man at the slop oil tank and the three men in the welding crew. Several million dollars worth of refinery equipment was destroyed.

These explosions clearly illustrate what I said in the first place; namely, that explosions may result from a chain of events instead of just one. Neither one of these explosions would have occurred if any one of the following things had not:

• The purchase of alky plant pump seals that were not appropriate for acid service;
• The failure to catch the error when the seals were first installed;
• Repeatedly installing the same type seals while expecting different results;
• The decision to store olefins in the slop oil tanks; and,
• The decision to disregard a special written order and pump hot slop oil into the tanks while they contained olefins.

Fifteen Words

I have been married 43 years (to the same woman). My marriage has been a happy one. Elaine and I have been blessed with three wonderful children and many good times. I read somewhere many years ago that there were only fifteen words that a man needed to know to have a happy marriage. No doubt there are other useful words to know as well, but the fifteen essential words are:

• I love you.
• You look great.
• I was wrong.
• May I help?
• Let’s eat out.

Okay, sixteen words if you insist on counting “Let’s” as two words.

Headin' Home

It was late August in 1962, and I was hitch-hiking home after camping out in the Rockies for more than two months with my oldest brother Lewis. We parted company somewhere in Montana, he on his way to LA to begin his new job and I on a very indirect route back to Albany, Georgia – did I mention that Albany was my home town? Anyway, the first leg of my trip home was with an M.I.T. classmate of Lewis’s named Jake. Jake was on his way back to Boston for more schooling, so I hopped a ride with him. Once I got to Boston, I turned south toward home. I didn’t hang around, because I was in a little bit of a hurry now -- I had to be at Tulane in a couple of weeks to begin my freshman year, and I wanted to spend a few days at home before then. I made fairly decent time for hitchhiking until I got to Philadelphia.

It was my strategy while hitch-hiking to wear a coat and tie, since surely that would make me look the handsome and wholesome young man that I was and help me get rides. I had just turned 18 about two weeks before. Camping out, Lewis and I had paid little attention to newspapers, calendars, and the like. Indeed, we rarely even listened to a radio, so it was a stroke of luck that I realized when my 18th birthday rolled around and we happened to be near Denver at the time. We stopped there so I could register for the draft. As I recall, it was the law back then to register within ten days of your 18th birthday. I think we may have eaten at a restaurant while in Denver.

But I digress. I was stuck in Philadelphia. I had known for nearly forever that Philadelphia meant the City of Brotherly Love, but after about eight hours waiting in vain for a ride, I was beginning seriously to question this common knowledge. After all, didn’t I have my coat and tie on? Wasn’t I clean, or at least as clean as you can be after camping out for two months? Didn’t I have my sign clearly stating what my target destination was? Why wasn’t it obvious to these people that I was just a young guy who needed a ride and that I posed no threat to anybody? (Did it occur to me that the locals weren’t who I should have been out of sorts with? Of course, but that didn’t stop me from being mad at the whole place.)

During my seemingly interminable stay in Philadelphia, I had moved from place to place to try to find a better spot to catch a ride. For the past couple of hours I had been standing at a major intersection near which a tall office building was located. After awhile I became aware that a man had come out of the building and was walking in my direction. As he got closer, I realized that he was indeed approaching me, apparently with the intention of opening up a conversation. He was, I would estimate, about 50 years old, and I was surprised that his first words were not exactly a greeting. Instead, he abruptly asked, “Why are you headed to Albany?”

Well, I was taken aback, and I was also somewhat annoyed. I mean to say, he might at least have said hello and made some small talk about how hard it was to hitch a ride those days or something. But he didn’t look unkind, and I saw no harm in telling the truth. I do that now and again, especially when it serves me no useful purpose to do otherwise. I replied, “I live there. I’ve been away for two months, and I want to see my mom and little brothers and sisters before going off to college next month.”

My answer visibly surprised him. He wasn’t inclined to believe me, and he asked me some more questions, among them being, “Haven’t you been reading the papers?” Well, of course, you know the answer to that. When I told him no, he asked me if I knew who Martin Luther King was. No, I didn’t have a clue. I mean, I knew very well who Martin Luther was, but Martin Luther King, Jr.? Finally, he said something like, “Well, he’s a Negro activist, and right now he’s with a lot of other Negros who are marching in Albany for integration and equal civil rights.” I think that in the end, it was my Georgia accent as much as anything else that convinced him that I wasn’t lying.

I knew the word activist from my reading, but I’m pretty sure that was the first time I ever heard anyone actually say the word activist out loud. Anyway, I finally – and instantaneously – became aware of what the problem was. I might not know who Martin Luther King Jr. was, but I sure as heck knew what the Supreme Court’s 1954 Brown vs. Board of Education decision was all about. Apparently its impact had finally reached my hometown.

The not unkindly man went on to explain that the sentiments of the local populace were for the most part inclined to favor the Negros’ position, and they (the locals, not the Negros) were not generally inclined to help someone suspected to be on his way to make trouble. And, he went on to say, that might be the way folks around there were thinking about me. “Wait here,” he said. “I’ll be back shortly.” Well, what else was I going to do? So I waited.

Twenty minutes later he returned with a sign listing Washington, D.C. as my destination. He advised me to put my Albany sign away until I got farther south. “Once you’re in your own territory, you can put your Albany sign back up.” Amazingly, it worked. For whatever reason, it worked, and I had a ride into Virginia before he made it back to his building. Bless him! Good ole city of brotherly love! From there on, it was smooth sailing until I reached Atlanta.

A trucker dropped me off at a restaurant there, and I walked in and announced, quite loudly, to the patrons: “My name is Philip Whitman, and I live in Albany, Georgia. I need a ride home. If anybody here is going there, I sure would appreciate a ride.” Reticence was never a strong suit of mine. After a minute or two, this fellow near the back of the restaurant called out, “What’s the name of the Albany High School football coach?” Well, now, I’m finally on my home territory I thought, as I replied, “Bernie Reid.” And without so much as a second’s pause, he said, “Well come on, let’s go. I can take you down the road a piece.”

He took me all the way to Zebulon, Georgia, which was only about three hours north of Albany on old Highway 19. Back then I-75 didn’t exist, and Highway 19 was the main road between Albany and Atlanta. That night I slept in the hayloft of an old barn on a farm in Zebulon, and the next morning I caught a ride before 8:00 o’clock. The guy took me all the way to my driveway. Boy, was I glad to get home!

Energy and Global Warming

I favor reducing our dependence on oil, especially foreign oil -- not because of global warming, but rather for national security. I think wind energy and solar energy, etc., are just fine if people want to invest in them, but I don't hold much hope for any meaningful contribution from these energy sources for several years, possibly decades, and I don't think we ought to be subsidizing their development and use with taxpayer money.

I think we should be doing more drilling for oil and gas, not less. We should be drilling more in Alaska and more off all three coasts, not just, or mainly, off the Gulf coast. We should be producing gasoline and gas from coal and shale, both of which we have in abundance, and we know how to do that. In fact, we have known how for a long time. To wit, a coal liquefaction plant was built in South Africa in the 1950’s, and in America coal gas was used extensively in the late 19th and early 20th centuries for lighting, cooking and heating. I think we should be building coal gasification plants and coal liquefaction plants. I think we should be tapping the huge shale gas formations in the U.S. However, I think we would be fooling ourselves if we thought doing all these things would be enough to solve all our energy problems.

I wish Americans would embrace the nuclear option. It seems to me far and away to be the most proven and economical energy technology, and we have plenty of uranium for nuclear fuel. Nuclear power generation doesn’t make carbon dioxide, in case that's what people are worried about. Americans like to make fun of the French, perhaps rightly so in some instances, but one thing I'll give them credit for, and that is that they have the energy thing down. They generate something like 70 to 80% of their power from nuclear plants, and they have had nary an accident. My understanding is that dramatic improvements have been made in safe design and safe operations since the Three Mile Island incident. With respect to disposal of the waste, why not bury it in lead containers within salt domes?

I think making ethanol fuel from corn is about the dumbest idea to come down the pike in several generations. (In sharp contradistinction, I think making ethanol for whiskey from corn has always been a great idea, but that is beside the point.)

As for global warming, I think it may be happening. However, I don’t think we have enough information to gauge how significant mankind’s contribution is, relative to that caused by the earth’s natural heating and cooling cycles. Moreover, I am doubtful as to how much we could do to stop it anyway, if it’s happening. After all, no other country would be required to adhere to any carbon cap-and trade law that America might enact, and it is my understanding that within a few years China alone is expected to be generating more carbon dioxide than the rest of the world combined. Finally, I think that if global warming is real, its effect will be gradual, giving people time to adapt, migrate to other climes, etc. Also, I think it would have some positive effects as well as some negative ones – for example, if some coastal lands were lost due to rising sea levels, then other coastal lands would naturally take their place, and land areas farther north would become more arable and habitable as a result of getting warmer.