Watershed Quiz 4

Question 1

SWE

Answer 1

Snow Water Equivalent: the depth of liquid water that would be released if all the snow in a snowpack were completely melted.

SWE=PsnowD
Psnow=density(gcm)
D=depth

Question 2

What is SWE measured with?

Answer 2

Snow tube

Question 3

Psnow=.2gcm
D=60cm

Answer 3

SWE=60*.2 = 12gcm
Pwater= 1g/cm
12gcm/1gcm= 12cm

Question 4

Snow accumulation factors

Answer 4

-weather
-elevation
-aspect
-wind
-vegetation

Question 5

Elevation effects

Answer 5

As elevation ⏫️ snow ⏫️
Trend is cause by
-⏫️ precipitation events due to orographic effects
-⏫️precipitation events due to snow
-⏬️ ablation

Question 6

Ablation

Answer 6

The total loss of water from a snowpack due to snowmelt, evaporation, and sublimation

Question 7

Snow accumulation - aspect

Answer 7

South aspect
⏫️energy
⏬️snow
North aspect
⏬️energy
⏫️snow

Question 8

Snow accumulation- wind

Answer 8

-redistribution of snow affected by vegetation. Cedar lowest wind speed pine forest highest
-loss of water by sublimation and evaporation

Question 9

Snow accumulation - vegetation

Answer 9

-increased snow in 2-5H gaps and openings
-if HD is considerably greater than tree height clearing may become wind swept
-snow packs melt earlier post harvest but these effects are short lived

Question 10

Interception

Answer 10

-process in which precipitation falls on and is held on terrestrial surfaces where it is subject to evaporation.
-HAS to evaporate to be considered interception

Question 11

Primary influences on interception

Answer 11

-Vegetation characteristics
-precipitation regime

Question 12

Th

Answer 12

Through fall- water able to infiltrate into the soil

Question 13

Pg, Pn

Answer 13

Pg= gross precipitation
Pn= net precipitation

Question 14

Ic, IT, Sf

Answer 14

Ic= canopy interception
It= litter interception
Sf= streamflow

Question 15

Total interception

Answer 15

Ic + It

Question 16

Net precipitation

Answer 16

Pnet = Gross precip(Pg) - all interception (I)

Question 17

Amount reaching forest soil

Answer 17

Amount reaching forest soil Pnet = Th + Sf

Question 18

Interception losses vegetation

Answer 18

Canopy storage
- conifers have more interception than deciduous due to higher leaf area index
- growing seasons have higher impact on interception than dormat seasons
- Spatial arrangement, SDI, crown closure
- crown form / branching habit
-bark form
-hydropicity

Question 19

Vegetation factors on precip deep dive

Answer 19

-clear cuts lead to less precipitation because of a loss of fog drip
-stand density ⏫️ then crown closure ⏫️ then LAI ⏫️ then interception ⏫️
-crown form
- branch angle ⏬️ then interception ⏫️(Douglas fir)
- branch angle ⏫️ then ⏫️ in stemflow and through fall(big leaf maple)

Question 20

Bark form

Answer 20

⏫️ bark roughness then ⏫️ in contact and surface area ⏫️ in bark storage water capacity and ⏫️ in interception

Question 21

Storm sizes and frequency

Answer 21

-more intense precipitation leads to less interception

Question 22

Interception storage capacity

Answer 22

The max amount of water held in all aerial portions of the vegetation or in the litter which may be subject to interception loss. Different species and vegetation types have different max amount of precipitation they can store

Question 23

What has more storage capacity rain or snow?

Answer 23

Rain

Question 24

Does older vegetation hold more water?

Answer 24

Yes they have higher interception capacities

Question 25

More storms

Answer 25

Less interception capacity

Question 26

Gross precipitation increases leading to

Answer 26

Interception to decrease. With more precipitation you have low vpd leading to less evaporation and high RH. also interception storage capacity has peaked

Question 27

What is the best date to snow survey?

Answer 27

April 1st because we assume snowpack is at its deepest