1. Studying TDS of Snow
Anne McLaughlin, Sam Putney, Jasmine Tang, Vincent Cullinan
Mentors: Mr. Tang, Mary Ellen, Nick, Spencer
Vince

2. Introduction We studied how particulate matter affects snow melting
Purpose: Help us better understand environmental science in terms of pollution and water conservation
We sampled 6 samples from 3 various sites around the ski lodge and compared the melt rates (high TDS vs low TDS)
Over a span of 2-3 days around noon
Anne
We studied how particulate matter affects snow melting
Purpose: If a higher amount of particulate matter does make the snow melt faster, we can better understand environmental science in terms of pollution and water conservation.
We sampled various sites around the ski lodge and compared the melt rates (high TDS vs low TDS)
To find this, we took 6 samples from 3 sites around the ski lodge over two days, looking at the PPM values, volume, pH values, and how fast the different samples melted
Over a span of 2-3 days around noon

3. Research Question Claim
How does the TDS of snow affect the melt rate of snow samples?
Claim
Hypothesis: increased levels of TDS correlates to faster snowmelt rates.
Anne: Our question was fairly simple, looking at the melting rates of snow based on the other particles within it.
To find this, we took 6 samples from 3 sites over two days, looking at the PPM values, volume, pH values, and how fast the different samples melted.
Jas Claim:
Hydrogen bond strength, lead this to lattice structure on next slide (talk about spacing it out and separating it)

4. Jas: particle perspective
Ice lattice structure may be rigid, but is spacious enough to allow for lots of air.
Explain how to ions will then be attracted to the hydrogen molecules (particularly elements in the second column and 7th column)

5. Procedure/Method Collected snow (∼125ml) from 3 different sites
Froze the snow we collected overnight
Melted the snow at room temperature
Tested ppm and pH of samples
Weighed the sample in grams
Froze them again
Timed the meltdown of the samples
Compared the melt rates of the samples to the ppm/pH of the samples
Looked for correlation
Vince
First, we collected 18 samples per day of about 125mL of snow. We tried not to pack it in, but for some of the older snow, we had to pack a little bit
Then, we put all these samples into plastic bags, and put them in the freezer to freeze and stay in a snow form
We then melted the snow at room temperature fully to liquid water.
Then, we tested the PPM and pH values of each sample, along with their weight in grams.
After, we froze them again
We then timed how long it took to go from ice (not snow) to liquid.
Finally we compared the differences between the pH levels and PPM of the two days of samples and the differences between refreezing.

6. Materials Hot plate and pot of water Balance/scale pH meter TDS meter
Thermometer
Plastic Bags
Timer
Plastic Test tubes/Beakers (mL)
Freezer
Snow
Vince
It’s a list. Read it.
pH: pH is a way to measure if a liquid is basic or acidic (phahhhhhh) higher is more basic and lower is more acidic
TDS: total dissolved solids

7. Locations
Vincent
These are our three locations. They are all pretty close together, but far enough, and with enough difference in human interactions and machines changed the TDS within the snow

8. Site #1 (Control/Top of Hill)
Sam: On top of the hill not far from the lodge and about 2 yards away for the treeline.
Reason:
Close to pure snow, and dig deeper to see if snow trapped beneath ice layers would contain purer snow

9. Site #2
Creek
Sam: Our second site was by a creek right next to this lodge. We chose this location because we were curious if any runoff this far downstream and close enough to smoke would cloud samples with pollution.

10. Site #3 Parking lot/Route 40
Sam: Our final site was at the parking lot near the lodge’s entrance and right next to Route 40. This location is key since many oils, gravel, and other particles such as salts thin the snow. High amounts of human activity would highly impact our TDS and pH testings in comparison to the cleaner snow

11. Samples:
Sam: These are the samples that we collected. Most are white and snowy, and relatively clean. The roadside sample, on the other hand, is very dirty.

12. pH Values
Sam: These are the pH’s that we found. As you can see the two days have little difference in median, but the second day had higher variation in their values.
Jas: talk about the variance in pH

13. TDS (ppm) Values
Jasmine: Big drop day 1 before and after (hypothesis):
Allow time to settle → precipitated ions are precipitated, TDS goes down because less ions found (not charged particles)
Proves more data is necessary for our sanity and graph

14. Melt Rates at Each Site Anne
We froze the samples inconsistently due to lack of time and we didn’t have enough time to recover

15. Melt Rates v TDS (Before) for Day 1 & 2
Anne on stats (Jas on explanation if needed): Because the R2 is so close to zero, this shows there were issues with our data which means we need to collect more data.
Top Left is from the creek, ones slightly below is from the control,and the other is from the Roadside. The data is all from Day 2. The weirdest point that is the furthest is from the roadside while the two closest are next to each other are the control and creek from Day 1. This proves more data is required. I actually attempted removing the weird point which honestly skewed the data more

16. Sources of Error Sample spillage Inaccurate beakers
Inconsistent freezing times and vessels
Inconsistent melting conditions.
Time inconsistency and constraints
Vince
We had some potential sources of error. Sample spillage was a problem as pouring water out of bags into small beakers is hard. To compound the issue, some of the bags and beakers also leaked Our beakers to measure the samples could have been much more accurate. We froze the samples for different amounts of time due to time constraints, which might have changed up melt rates The water temperature in which we melted the snow varied slightly throughout the duration of the experiment due to the hot plate not being able to keep the water in the pot at a consistent temperature. Our first samples were melted within a test tube, to make them all the same size and shape, with the same surface area. The second samples were frozen within the plastic bags, and has different surface areas, which changed how fast they melted

17. Additional Research 1
A recent study proves dirt accelerates melt rates in snowpack
“The Real Culprit Behind Snowmelt Floods isn’t Temperature—it’s Dirt”
Dirt darkens the snow → snow absorbs sun’s energy faster
“Temperature now accounts for about 10% of the energy that melts snow”
Temperature isn’t as huge of a factor
Anne:
Colorado snow is continental and much different from maritime snow

18. Additional Research 2
Energy.ca.gov article “Mechanical Freeze/Thaw and Freeze COncentration of Water and Wastewater Residuals”
Electrical Power Research Institute in Palo Alto → Jan 2002
Main goals: how economical is this process?
About removing waste particulate from raw water
Using biofreeze to separate organic from inorganic
Relation to our TDS results and ion filtration → precipitation
Results: highly efficient process
Power results inconsitant
Jas
Relate back to TDS and filtration
Chemicals fitrated = alum, lime, and ferric chloride

19. Future Research
More samples taken over a longer period of time would allow us to stabilize the data more and look for trends
Potentially look at the effects of different weather on the melt rates and samples.
Sam: Some points that we could have looked into if we had more time was creating a larger sample size and looking at how weather affects the melt rates.

20. Reasoning Increase of PPM day 1 Decrease of PPM day 2
Day two samples melted faster from inconsistencies
Rain and runoff possibly changed day two data
Day one data supported our claim
Day two created discrepancies
Jasmine/Sam: Day one had an increase in PPM after melting, while day two had a decrease. Day two samples also melted significantly faster than the day one samples. Rainy weather may have played a part in this bizarre discrepancy.

21. Questions?
Vincent

22. Works Cited
DenglerFeb, Roni, et al. “The real culprit behind snowmelt floods isn't temperature-It's dirt.” Science | AAAS, American Association for
the Advancement of Science, 1 Feb. 2018,
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“Task 2.6: Mechanical Freeze/Thaw and Freeze Concentration of Water and Wastewater Residuals.” Task 2.6: Mechanical Freeze/Thaw and Freeze Concentration of Water and Wastewater Residuals, Jan. 2002, < / _A6.PDF.>
ANNE: Thank you for your time!