Science is really not as hard as you think. We are all observers, which is the basis of science, and thus all have a little, or big, scientist lurking inside us. This book is meant to unleash your hidden scientist, letting the geek free and in the process helping you understand and eventually take action on the great processes that form the world around us.
Take temperature, for example. From a basic standpoint, it equates to the energy stored and released from a material or a system. We all experience temperature, and know how it is measured, what those measurements mean, and we interpret and apply that data to our own lives. For example, if it is cold outside, we wear a coat so as not to waste so much energy keeping warm—a burden of having this mammalian body that is great at keeping its temperature stable and high so that we remain active in any environment but really wasteful compared to the metabolism of a tortoise.
Take another temperature example of physics, in this case our understanding of heat loss. We are all afraid of physics, but on some levels it is the most intuitive of sciences. Let’s look at the physics of a hot cup of coffee.
We feel energy loss from a hot cup of coffee, as the liquid is “trying” to achieve the same temperature as its surroundings (entropy). It is using the process of diffusion, relying on molecules to move within the liquid and transfer their excess heat energy to their surroundings. We can accelerate this process by actively mixing the coffee, which brings more of the hot coffee into contact with the less hot air above it and the cup around it. This is using the process of advection, moving the material and its molecules to actively move the excess energy off the coffee. We intuitively know this physics of energy, diffusion, and advection even if we don’t necessarily know the terms.
Now let’s take a solid, like ice. Ice is cold, obviously—in fact, it is 0 degrees, and serves as the very basis for the Celsius temperature system. When we put ice into a glass of water, it will slowly melt, in essence absorbing the heat in the water around it, as the ice turns from a heat-depleted solid to a liquid state. We all know this basic aspect of the energy properties of ice and water, even without knowing the terms for heat of condensation, for example.
This intuitive knowledge from the experiment in your drinking glass can be translated to the outside world, with really interesting results.
Consider a glacier, which is effectively a “river” of ice that flows from a source, where it is cold and has some snow accumulation, down to a terminus—think those tremendous pieces of glacier breaking off the cliff face at the seas edge in Alaska.
You might not know that a glacier is pretty hard to melt. Even when the potential temperature above a glacier should be above 0 degrees, it is not in fact 0 degrees. This is because of another property of physics—in this case, color.
Black materials appear black because the chemicals or minerals in that material absorb light over the full spectrum of colors, which are the optical manifestations of wavelengths. The fact that they absorb light, and hence the energy from that light, is well known intuitively to us. Walking across black asphalt in the summer can feel like walking across hot lava. And there is nothing like sweating under the hot sun in a black shirt to make you rethink your summer fashion choices.
Ice and snow are white—they reflect a lot of the light they receive. In fact, they reflect almost ¾ of the energy they receive from sunlight right back off the surface and back out to outer space, before anything has a chance to capture that potential solar energy. That is unless you happen to be snow skiing, in which case your skin can at least catch some of the ultraviolet rays bouncing off the snow. This provides the double whammy effect when you snow ski of getting sunburnt from above and from light reflecting off the slopes from below.
This balance between absorption and reflection has a scientific term, of course—albedo, which is a measure of how much light energy reflects off a surface. Something that absorbs 100% of light it receives, meaning that it reflects 0%, has an albedo of 0, whereas a material with the opposite characteristic has an albedo of 1. There are various mathematical reasons why the 0 to 1 scale is more useful than the 0-100% scale, so it is not a case of scientists being cruel! But back to ice…
Ice has a high albedo—about 0.7. So when sunlight hits ice, much of the energy is reflected right back out to outer space. When sunlight hits asphalt, which has a low albedo of about 0.3, much of the energy is absorbed, and the asphalt gives it off by heating the air above it.
So when sunlight hits ice, the air above the ice is actually cooler than would be expected compared to average absorption. In this way, ice inadvertently “protects itself” from melting, even when it really should be melting based on the amount of sunlight it is receiving. The air temperature has to increase quite a bit around ice to overcome this physical property of energy absorption and begin melting. The ice uses physics as a form of life insurance!
All relatively straightforward applications of basic principles of physics, but with a very intriguing implication for climate change. As air temperatures are warming because of human activities (trust me, there will be much more on this later!), they have begun exceeding the ice’s capacity for self-protection, and ice worldwide has begun melting.
The interesting thing about this melting is that it is a very non-linear response. A linear response is a response proportional to a force—think pushing a glass across your kitchen table. A gentle push will move the glass a short distance, and a harder push will move it farther. The non-linear response comes when the glass reaches the edge of the table. At this point, even a gentle nudge will send the glass over the edge, resulting in it moving a great distance, at a great speed, as it crashes to the floor. I strongly encourage you to experiment with this right now, hopefully using a soda or milk that will be particularly hard to clean up…
Back to ice and non-linearity. The slow warming causes some melting at the edges of a sheet of ice, the linear response, but as the edge of this ice sheet begins to erode, it loses its high albedo (assume that there is rock underneath, with a low albedo so high heat absorption capacity). This causes the air on the edge of the eroding ice sheet to heat up even more than it would otherwise, causing increased rates of melting, more exposure of rock, more absorption of heat, more melting, and so forth.
Global ice is a glass that we have inadvertently moved close to the edge of the global table. Continual gradual increases in air temperature are the gentle push that is causing ice sheets to tumble off the table, crumbling and melting and retreating the world over. We don’t know exactly there the table edge is—in other words, how much more heating ice can take before “going non-linear,” but based on recent satellite observations, we think that we are almost there.
Not only does this mean a changed, increasingly ice-free planet, with serious concerns for global water supplies for us (oh, and polar bears are getting pretty pissed off too), but it also means that we are exposing much more low albedo materials, like rocks and seawater to absorb even more energy from the sun. Do you hear that runaway train rumbling down the track?
This provides a few relatively straightforward examples of how we can use some of our intuitive understanding of physical and natural processes to explicitly understand current issues that we are all facing. Through our understanding of these processes, we can make better and more informed decisions about how we live on this planet, and can better direct our planet on a trajectory that we want.
The recent favorite pastime of politicians who want to avoid even discussing issues related to human induced global warming is to say “I am not a scientist.” This call has been taken up by some of my scientist friends, who respond with “That’s OK, because we are” and hence move the discussion forward. Although I like this approach, a response that I prefer is “But sir/madam, you are a scientist—we all are!” We all use data to inform our interpretations of response and thus personal decisions—my outside thermometer lets me decide whether I should wear a sweater today, even before I test the weather outside.
Of course, I no sooner expect you to understand the intricacies of global phosphorus cycling (my expertise) than you should expect me to understand and explain string theory (probably not your expertise, either!). But most of the great processes that drive our planet, and current issues about how we as humans and a global society interact with these processes, are straightforward, and can be adequately described in ways that nearly everybody can not only understand but can own and take informed actions on.
The political “I am not a scientist” statement is employing willful ignorance to avoid making informed, and perhaps contentious, decisions. I don’t buy it—ignorance of science will not make science go away. Nor will it easily make 2+2 equal to 5, no matter how much that Orwellian trope pervades many public discussions of science.
As you can probably glean from the above, this book is not intended for Biblical literalists, or literalists of any scripture. If you are, I don’t have time for you. Your eyes are too tightly closed to observe the relatively simple but endlessly miraculous patterns of nature around us. Some would like to think that the miraculous is just more mysteries that we may eventually solve, and some believe that the miraculous is a reflection of God’s presence or will. Either way, exploring the miraculous should not be forbidden, but rather exulted as part of our unique role on this planet.
So, if you think that the world was created 6,500 years ago, or if you believe that dinosaurs and humans co-existed, do not read this blog—I have nothing to give you. Oh, actually, please do read this blog, tell your cult/group/flock to also buy this book when published, and organize a public and highly advertised book burning ceremony, showing your resounding defeat of logic and sensibility in the face of clear proof from your literal scripture. I would love the book sales, because how else am I going to move a book that is trying to instill geekiness back into popular culture!