Friday, October 23, 2015

It's a Science Blog! Part 2: Methane, Mooing, and Mires


On the last edition of It’s a Science Blog! I introduced the Arctic, permafrost, and carbon (I know it has been a while. I haven’t been procrastinating, I promise. But for a refresher just keep scrolling!). In this edition I will venture a little deeper into greenhouse gases and what they have to do with my project here in Sweden. Exciting stuff.

To start, I want to look back at a term I threw out in the first blog, greenhouse gases (GHG). This word gets used a lot when talking about climate change and I want to take a second to break it down a little bit. Greenhouse gases are compounds that, when present in the atmosphere, act to trap heat and warm up the earth. You are probably most familiar with the GHG, carbon dioxide. Carbon dioxide (CO2) is produced from fossil fuel combustion (burning coal, oil, natural gas), but can come from natural sources. For example, we release CO2 when we breath. But CO2 is not the only greenhouse gas. Other common GHG include water vapor, nitrous oxide (also produced by your car!), and methane (CH4).

Together, these gases let some types of light waves, known as UV light, through the earth’s atmosphere, while trapping another type, called infrared radiation (IR radiation), sending it back to the earth, heating the atmosphere. A similar process happens in greenhouses we have for plants, thus the name!
 
Greenhouse gases trap IR radiation (heat) coming from the earth and send it back towards the surface

My research centers around methane (I also look at CO2 as well, but I won't go into detail about that here), which is close to 20 times more effective at trapping heat than CO2. You might be thinking, hey methane… cows produce that when they burp, right? Yep, but hold on, I’ll get to that. First, some background info.  

Methane is a product of metabolism by a group of small organisms called methanogens. In other words, really tiny critters eat carbon and produce methane as waste. But for this to happen, methanogens have to be in an environment with no oxygen. Where do these environments exist?... Well, a lot of places actually.

For example, in nature, environments with little to no oxygen ("anoxic" environments) can be created when the ground becomes saturated with water which cuts off the soil from the oxygen in the atmosphere. So you can imagine how the bottom of a lake is a very anoxic. But you don’t even need an entire lake to have these conditions. In fact, wetlands and rice paddies are some of the leading sources of methane.

Man-made landfills also create an anoxic environment perfect for methanogens and methane production. The food we throw away into landfills builds up so much that we have to compress the trash in the landfill, leaving the bottom of the landfill with no oxygen. Then our leftover food becomes the main meal for methanogens.  

Methane is produced both by natural processes and human activity- for example, landfills. 

And where do cows fit in all of this? Well, it turns out, a cow’s stomach doesn’t have a whole lot of oxygen either. Methanogens are able to live inside the cow's stomach, breaking down food and turning it into methane just as they do in anoxic landfills and wetlands. The methane is then released into the atmosphere when cows burp.

Okay, enough about cows. Let’s get to the question you have probably been asking for a while… what am I doing? Yes, what am I doing- in life, in Sweden, in general. Good questions. I don’t actually spend all my time hiking in the mountains, as it may appear. Till just recently, I have spent most of my days outside mucking through a mire and loosing my boots to mats of quicksand-like mosses.

 A mire is a type of wetland. In the mire I study, there are both patches of low lying, soggy or water covered ground (where the boot gobbling, quicksand mosses live) and higher patches of dry ground. Most generally, these high patches, known as palsas, contain permafrost (don’t know what permafrost is? Check out my previous science blog!), while the low, wet patches are mainly permafrost free. My project focuses on small ponds in these low, permafrost-free regions of the mire. I want to know if methane is being produced and emitted from these ponds, and, if so, how much methane is being emitted and how it compares to the emissions from nearby lakes and streams.  But… I think that’s enough for today. More methane-pond-mire breakdown in the next It’s a Science Blog! For now, enjoy these pictures of Stordalen mire, my workplace:







Oh, and for those of you wondering why methane hydrates, natural gas, termites, giant Siberian sink holes, methane on Mars and other methane related topics didn’t make it into this blog, I am not ignoring them. There just isn’t enough room in one blog to fit every cool topic concerning methane. But if you want to talk about these topics just email me! I’m always down for a methane chat.

-Kenzie 

This site is not an official Fulbright Program site. The views expressed in this site are entirely those of its author and do not represent the views of the Fulbright Program, the U.S. Department of State or any of its partner organizations.

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