How should I brace myself for climate change–besides investing in deodorant? Seriously, what are the impacts of climate change besides getting warmer?
This “Hear the Big Picture” podcast addresses what climate change is all about, whether Earth is really getting warmer and why, and what else is going on.
Maria: The circumstances that make the environment warmer are having many other negative impacts, and while almost everyone feels the heat, there is still controversy about why.
Jane: Does this have to do with the “greenhouse effect?”
Maria: It sure does. Physics teaches us that it’s possible to have a barrier that heat can enter but not leave. We call this the Greenhouse Effect. If you grow vegetables or flowers in a greenhouse, the glass walls trap the heat inside. So the greenhouse stays warm which benefits the flowers or vegetables being grown there.
In the context of the Earth and its atmosphere, greenhouse gases like carbon dioxide comprise the barrier. They trap the heat inside the earth’s atmosphere which in turn warms up the Earth.
These greenhouse gases are a byproduct of burning fuels which we do for energy. And since we continue to burn fuels, it follows that we can expect the earth to just keep getting hotter and hotter.
You have to understand that this is the problem from hell because it’s everyone’s fault, but no one can do much about it. That is, no one individual can make a big difference in solving the problem with their actions. Some people don’t want to give up their comfortable life-styles when they know that would barely make a dent in the problem.
And on top of that, as populations become more prosperous, many people aspire to a lifestyle that will make the problem even worse.
Jane: How did we first become aware of this issue?
Maria: There are two parts to this answer—-when the scientists became aware of it and when the public started paying attention to this matter. At some point in the 1900’s, scientists began to wonder if some human activity could cause a Greenhouse Effect on Earth. So they started measuring Earth temperatures in the 1950s. And indeed they found evidence of rising temperatures. That is, scientists used their knowledge to predict something they had not yet observed. Then when they looked for it, they found it. That is, they found rising temperatures. It is important to understand that this is the most powerful and credible type of scientific discovery possible.
Jane: OK…..And when did the public become aware of this?
Maria: I think it started to be a big public issue around the time of Hurricane Katrina in 2005. There was a lot of argument about climate change then. Some people insisted, “We have no evidence that climate change caused Katrina.” Other people said that humid air above a “warmer than ever” Gulf of Mexico must have made Katrina’s impact worse than it would otherwise have been.
Jane: Getting back to the scientists, do they mostly all believe that the Earth is warming?
Maria: At this point almost all of the scientists believe this.
Jane: So has the scientific majority convinced others that they are right about the earth getting warmer?
Maria: We have ample evidence that scientists successfully convinced many people of this years ago. For example, strategic planners in the Department of Defense worked for years on how to defend the United States as the ice melts and the Arctic becomes navigable. There is a big Russian border on the Arctic Ocean and if those waters can be navigated, it exposes people in the United States to new sorts of security risks.
The point is that if the Defense Department hadn’t been convinced that global warming was really happening, they wouldn’t have spent time and money planning for how to deal with resulting security risks.
Jane: If so many experts believe this, then why is there so much controversy about the subject?
Maria: Well, the big question is not whether the earth is getting warmer, but whether it’s getting warmer because of human activity or for some other reason. This is the crucial point: The controversy is really about why, not whether, this is happening. In other words, we must ask if there is something in nature that is going on or if it’s due to us humans.
We know that during the long history of the Earth, that its climate has changed several times. For example, in the early Ice Ages, the Earth got much colder. But that was clearly not due to human activity, because humans were not around at that time. So, we know that it’s possible for the Earth’s climate to change naturally, and not due to human activity.
What is important is that the current climate change is happening much faster than it would if it were due to natural causes. So it’s no surprise that the overwhelming majority of scientists today are convinced that human activity is the cause of the current warming.
Jane: Then why is there so much resistance to accepting that we need to make some changes to deal with this problem?
Maria: Some people have a lot to lose if we all conclude that climate change is caused by burning fossil fuels. Whenever we make technological changes, there are winners and losers; some industries are helped and others are hurt.
The point is we have to get our energy from somewhere to enjoy the standard of living we are accustomed to. It must either come from burning fuels or it can come from the sun, the wind or nuclear sources. But again, there are commercial winners and losers whenever you change technologies. So a reduction in burning these fuels, which we call “fossil fuels,” will always hurt some segment of the population and it will help others.
Jane: What exactly do you mean by fossil fuels?
Maria: Fossil fuels are products made from oily materials that are mined from beneath the earth. These extracted materials are mostly coal, natural gas and crude oil. They are the raw materials for energy products we use everyday— for cars, trucks, and railways and for heating for our homes, offices, and factories. Whenever we burn fossil fuels, we manufacture carbon dioxide as a byproduct. Burning wood for heat also creates COs, although wood is not a fossil fuel.
Jane: I see. I remember from high school that CO2 is also called carbon dioxide. And in the news I hear it sometimes just called carbon. I assume these all refer to the same thing, right?
Maria: Yes; that’s right.
Jane: So then, the CO2 traps heat and makes the Earth warmer, right?…
Maria: Yes. Commercial interests that benefit from hanging on to fossil fuels are certainly not anxious to create regulations that would minimize their use. We have to appreciate that this is a situation that guarantees controversy no matter how much scientific data we collect.
Jane: There is something about this controversy that confuses me. Hasn’t there always been CO2 in the atmosphere?
Maria: Yes but fossil fuel consumption vastly increased the amount of CO2 in the atmosphere since the industrial revolution started in the 1800s. And it has gradually been affecting the atmosphere. We just didn’t really take notice until more recently.
Jane: So this CO2 makes the atmosphere warmer…
Are there other impacts on the climate besides just getting warmer?
Maria: Yes there are three major impacts: extreme weather events, sea level rise, and acidic oceans. Sometimes when we talk about global warming, that’s really a shortcut for the larger term of climate change which includes all three of these sobering changes.
Over the years, climate scientists have developed computer models to try and predict the future impacts of climate change. Computer models are a way of using recent data to extrapolate and get a glimpse of what is expected in the future.
The model predictions we have show that as the planet gets hotter, dry places will get drier and wet places will get wetter and there will be more extreme weather events! This is not a pretty picture.
We’re already seeing more wildfires out in the western United States. We’re getting less rainfall in these areas which makes the forests drier. As a result, they are more likely to catch fire and burn. And on top of that, the areas that are extremely dry like deserts, are getting bigger.
We’ve all seen that there has been an increase in severe weather events. In the Gulf of Mexico, there were three back-to-back hurricanes in 2017: Harvey, Irma, and Maria. As you know, we’ve always had hurricanes. But most scientists believe that climate change worsens their impact even though it doesn’t cause them.
Jane: Wow. Scary stuff!
Maria: One of the theories about Hurricane Harvey’s severe impact on Houston is that the air currents moved over the land much more slowly than they used to. It seems that wind patterns and air currents like the Jet Stream have changed due to climate change.
Scientists think that Hurricane Harvey was caught up in a slow-moving air current, so a much greater amount of rain was dumped on one particular place than normally happens. We are not really sure about this but some scientists theorize that without climate change, the wind and rain might have moved more quickly so the rain would have fallen over a broader area rather than dumping so much in Houston. This would have made the flooding much less serious.
Jane: So let me see if i get this…. So….climate change isn’t just warming things up a little. You’re saying many people’s lives have already been adversely impacted. We’ve seen the devastation caused by those hurricanes. And I have also heard that some successful vineyards in northern California have burned down from the lack of rain.
This is feeling a little overwhelming. Are there any other impacts I should brace myself for?
Maria: Another big change is that sea levels are rising as ice melts. Ice caps that are above sea level near the north and south poles are melting due to the warmer temperatures. The poles are getting warmer faster than the tropics. That is what the models tell us. As a result of ice melting, there’s more ocean water, which causes a rise in sea levels.
It’s important to remember all the oceans are connected so the rise in sea level happens across the entire globe. And to make matters worse, like most liquids, water expands when it becomes warmer. Every single “drop” of water on the planet expands a little tiny bit as the temperature goes up. So we have both more water and water that takes up more space—further contributing to a worldwide rise in sea-level.
Jane: Wow. I know that things expand with heat. But I never recognized that this principle applies here.
Maria: People who live near the coasts anywhere in the world are at risk of losing their homes to flooding as a result. There’s an estimate that in the future, thirty million people will be displaced in Bangladesh because their homes will be underwater.
The city of Miami in Florida has the same issue; they have particularly low elevation. Miami has bought pumps just to pump the water out of the streets after a rain. But that isn’t a real solution; it’s a band aid. The water comes right back, and I understand part of Miami now even gets flooded in some places just from medium sized rain showers. It doesn’t require a hurricane to cause problems.
But the problem doesn’t apply just to a few cities. It’s an issue for anyone living near the coasts. Imagine the economic and political consequences of people becoming homeless due to the weather!
Jane: Wow. Climate change has a lot of scary ramifications.
Maria. Yes… It makes hurricanes more fierce; it makes some areas dry to the point of becoming deserts, and wildfires become more likely; plus it puts people’s lives and homes at risk if they are near the ocean. And don’t get me started on ecology… This doesn’t even begin to address the impact on wild animals and plants and their inability to cope with these rapid changes.
Another impact of climate change we haven’t talked about is that oceans absorb some of the increased carbon dioxide in the atmosphere that results from burning fossil fuels. The CO2 reacts with the water to form carboxylic acid—making the oceans more acidic than they used to be.
Jane: What is the problem with the ocean becoming a little more acidic?
Maria : The problem is this will make it harder for lobsters, clams, and other shellfish to form their shells. They may die or have fewer offspring. Besides acidity, another adverse impact of global warming on the ocean is that coral reefs are deteriorating everywhere. These changes in acidity and temperature really affect all ocean life.
Jane: Are there any sources of climate change beside CO2 created from burning fuels?
Maria: CO2 is the most common greenhouse gas, but there are others. Natural gas, which can leak from anywhere it is found or used, causes further global warming. There are other gases which do this too, but they are less common.
People may wonder whether they personally should be concerned. Since we continue to burn fossil fuels, we can expect the earth to just get hotter and hotter. We will explore further the impact of this in our next podcast—and reasons for optimism in dealing with this crisis.