Week 3

Hello my fellow Americans!

     This post is going to be substantially longer and dryer (pineapple?) than those in the past as there are a lot of graphs and technical things. But bare with me, learning is cool if you stay in school! Ha see what I did? I just made that rhyme up myself!
     I apologize for making my 3rd week post so late (yes, it is the beginning of the 4th week), but I did use today's snow day to catch up on work.
     First, I got equations for how to measure how much rainwater we can actually collect from our roofs (obviously, one of the most important life questions always burning at the back of our minds). In a rainwater harvesting manual created by U of A students, the amount of rain we can collect is:

Rainfall (in) x 0.623 x Roof/ catchment Area (ft^2) x Runoff Coefficient

     The runoff coefficient is what percent of the rainfall can be harvested, depending on the different materials the rain runs off of (e.g. roof vs. paving vs. gravel). The .623 refers to how many gallons are in one inch of rain per 1000 square feet (623 gal). This equation will be helpful when I measure rooftops.

     This past week, I got data on precipitation for the last 30 years (1985-2014), recorded at two different "stations" in and around the city (Flagstaff Pulliam Airport and 4SW). I will get those spreadsheets up and running asap! I do have to give huge credit to my father for finding the records and Ms. Vaughan for helping throughout the day, because I do have to admit, I did end up staring for several long minutes in pure awe at the majestic space table at which we had our last group meeting... Well, since I'm giving you readers my full attention, I then took those values and calculated the monthly, decadely (is that a real thing?), and overall averages and compared to the two station. Using excel graphed all that junk and "drew" a linear trend through each. Here's what I discovered for Pulliam: the averages for each year:

Each decade:

Past 15 years:

Averages for 4SW:
Each year:

Each decade:

Past 15:

     First (as you can see with your fabulous eyeballs), although many of the points seem very spread out and sporadic--especially in the 30 year graphs--most of these trends show a decrease in precipitation (oof..). To quote the Magnificent Meilbeck, "Muy mal!" Now, the trend of the point being seemingly random, this is mainly due to the fact that the climate of Flagstaff has a very high variance from year to year. I suppose this can be seen throughout a single year too--I mean c'mon, blizzard one minute, 80º the next? What's the deal weather gods?! Getting technical, I used standard deviation on the averages at each station with each approximately 6.5. For all of you who are not math geeks, standard deviation (usually associated with variance) discovers how spread out data points are from the mean. Anywho, both of these stations also showed nearly identical trends. But one interesting thing I noticed is how that trend (based on the averages) actually increased at Pulliam! I hope to discover why, exactly, this is the case but one hypothesis I have is that Pulliam may be more exposed than 4SW, and thus is able to collect more precipitation on average! Finally, these graphs not only show recorded precip. but also that though the two stations represent very similar data, there is still variance between the two.
     My last point about variation, one thing to take into consideration is the rainshadow effect. I'm not the only one seeing that huge mountain to the north right? Well, the main idea behind this is that warm, moist air is pushed up the side of a mountain (in our case, usually from the South or Southwest). It then cools and condenses, creating clouds, from which all of that water in the air falls. Now, the air keeps moving, it plays by its own rules cause it ain't got time for any shenanigans. It has places to be, people! But this air is now dry so the other side of the mountain gets little to no precipitation. This can definitely be seen in the reports from Wupatki and Sunset Crater stations.
Wupatki:

Sunset Crater:

The precip. decrease is definitely sharper here, due to the effect I described above! Any exposed groundwater is also more quickly evaporated in this area because of the dry wind, making it a more arid landscape. So the Pulliam and 4SW are more representative of the city of Flagstaff rather than Doney Park or other northern communities. Later on, I hope to calculate the exact trend and utilize it to predict a range of precipitation for the next 10 years.

Alright, almost done guys!
     The past week, I have also been working on measuring rooftops in the Fox Glenn neighborhood.

     I chose this neighborhood rather than "Townsite" because: 1) it's newer therefore there are slightly less tress obstructing rooftops and 2) it has more medium sized homes, and thus, represents the "average" home for Flagstaff. Furthermore, I use tools in Google Earth Pro to place points on each roof, creating some freaky polygon, the area of which is calculated for me! Psh, measuring things by hand was so 2000... Anywho, amazing examples from yours truly:

Pretty neat, huh? 

     One problem I came across is that trees covering certain roofs and poor resolution made it difficult to get more accurate measurements I will take the average and use the rainfall equation above to calculate the average amount of rain the plebeians of Flagstaff can harvest!
     Well, though this post was very technical, I hope you found that helpful and informative! Thank you for taking the time to read this and please feel free to leave a comment :)
                               -Lia