Quiz 1(Geo 155 Discussion section)

Why is there so much more difference between latitudes in the winter than in the summer?

Because of Earth's tilt (it is Eather close or far away, while the equator stays generally in the middle), and in the winter, days are shorter with less direct sunlight, while n the summer, days are longer with more direct sunlight the seasonal changes in climate are caused by the varying angle of the sun's rays, together with the varying amount of time that the sun is above our horizon.

At what elevation will condensation begin?

Condensation will begin at 500 m because this is where the air hits it's dewpoint (10 C)

Saturated Adiabatic Lapse Rate (SALR)

used if rising air is saturated and condensation is going on because the release of latent heat changes the rate of temperature change. The SALR thus varies depending on the amount of condensation occurring, but for this exercise, we will assume a constant rate of .6 degrees Celsius / 100m

Longitude

(meridians) not parallel but the same length

Latitude lines

(parallels) Parallel and not the same length

Santa Lucia Mountains Consider a parcel of air arriving at the Big Sur coast with a temperature of 15 degrees Celsius and a dewpoint temperature of 10 degrees Celsius. Because air here generally moves from west to eat, it can be expected to pass over the Santa Lucia and drop down to King City. Keep in mind what is happening in terms of adiabatic processes, and assume that any water that condenses will fall out of the air as rain.

0 m (ELR) = 15 degrees Celsius 500 m = 10 degrees Celsius (use DALR to subtract 5 degrees Celsius) 1000 m = 7 degrees Celsius (use SALR to subtract 3 because air became saturated at 10 degrees Celcius) 1500 m = 4 degrees Celcius 1000 m = 9 degrees Celcius (Plus 5 because the air is warming as it sinks. lose saturation because it has precipitated on the other side) 500 m = 14 degrees Celcius (plus 5 DALR) 100 m = 18 degrees Celcius (plus 4 because can only go down/ stay / can't go up as temperature goes up

If a parcel of air has an absolute humidity of 4.7 g/m^3, and a temperature of 10 c, what is its relative humidity?

10 = 9.4 (g/m^3) (saturation humidity at 10 degrees Celsius) R.H = 4.7/9.4 x 100 R.H = 50%

How has the temperature and actual humidity of the air changed between Big Sur and King City?

15 - 18 (humidity has dropped, other side of the mountain, King City, is the rainshadow) Big Sur climate: cooler, more humid, and wet King City: dry and warm

Temp of the air at King City?

18

If the parcel is warmed to 25 c, without adding or removing water vapor, what will be its relative humidity (approximately)?

25 c = 23 S.H R.H = 4.7/23 x 100 RH = 20.4%

Dewpoint temp at king city?

4 (once hits the peak, doesn't change because the dewpoint can only go down and can't go up as temperature goes up)

What will the relative humidity of the air be at the crest of the mountains?

4 degrees Celsius = dew point - dew point at 100% (dewpoint will always going to match the temperature when saturated) (as temperature drops, so does the dewpoint)

What will the air temperature be at the crest of the mountains?

4 degrees Celsius at the top

CO2 is considered a greenhouse gas, what does this mean, and why does it affect global average temperatures?

CO2 is a greenhouse gas because it traps in the Earth's heat - it doesn't allow longwave radiation to pass it (that the Earth is emitting).

Plotted on the right are Mauna Loa CO2 levels each month for an entire year. Why is there such a contrasting trend at the seasonal scale compared to the long-term trend?

Carbon sinks change throughout the months as well as human activities. And measuring in small data amounts will only show a small section of what is on average increasing over a long period of time.

What is the dew point of a parcel of air with an absolute humidity of 10.2 g/m^3?

Dew point temp = 11

Fill in the chart to indicate the solar altitude (sun angle at different latitudes throughout the year.

NP: DS: 0, ME: 0, JS: 0-90, SE: 0 AC: 0, 0-90, 0-90, 0-90 TOCan: 0-90, 0-90, 90, 0-90 E: 0-90, 90, 0-90, 90 TOCap: 90, 0-90, 0-90, 0-90, 0-90 AC: 0-90, 0-90, 0, 0-90 SP: 0-90, 0, 0, 0

Fill in the chart to indicate the day length at different latitudes through the year.

North Pole: DS: 0, ME: 12, JS: 24, SE: 12 Arctic Circle: 0, 12, 24, 12 Tropic of Cancer: 0-12, 12, 12-24, 12 Equator: : 12, 12, 12, 12 Tropic of Capricorn: 12-24, 12, 0-12, 12 Antarctic Circle: 24, 12, 0, 12 South Pole: 24, 12, 0, 12

What is the general trend in average CO2 and average global air temperatures?

Positive slope.

If a parcel of air has a relative humidity of 50% at 15 degrees C, can you determine the dew point temperature?

RH = (A.H/S.H) x 100 RH= (AH/SH) SHxRH = AH AH = RH x SH 15 degrees Celsius = 12.8 SH .5= x/12.8 DP = 4.9 degrees Celsius

dewpoint temperature

The temperature at which, for a given absolute humidity, S.H. = A.H., causing R.H. to be 100%

How closely do the temperature and CO2 levels appear to be related? What does this suggest?

Strong correlation. CO2 is the cause, effect is the temperature increase (as CO2 levels increase, so does temperature).

why does the Southern Hemisphere receive slightly more radiation in their summer and slightly less radiation in their winter than the Northern Hemisphere?

The Southern Hemisphere is closer to the sun in the summer and farther from the sun in the winter. The Northern hemisphere is farther from the sun in the summer and closer to the sun in the winter The Southern Hemisphere receives more energy during December (southern summer) than the Northern Hemisphere does in June (northern summer) because Earth's orbit is not a perfect circle and Earth is slightly closer to the Sun during that part of its orbit.

Saturation Humidity

The amount of vapor that the air has the capacity to hold at a given moment based on its temperature

What is Humidity?

The amount of vapor thats actually in the air

What conclusion does this graph suggest how the annual range of radiation varies across latitudes?

The annual range is greater at higher altitudes (70 degrees North has a greater range, while 20 degrees North has a less range of radiation), and there is less of a range towards the center. As altitude increases from the equator, the average daily solar radiation varies more and more with more extreme differences in radiation exposure throughout the year.

Absolute Humidity

The mass of vapor per volume of air (grams per cubic meter)

Relative humidity and how to calculate it

The ratio between the actual humidity of the air and its saturation humidity R.H. = (A.H./S.H.) x 100

Saturation curve

a graph displaying how much water vapor a parcel of air can hold at different temperatures

The Keeling Curve

a graph which plots the ongoing change in concentration of carbon dioxide in Earth's atmosphere since 1958. The global average temperatures from a vast amount of data is converted to annual anomalies by calculating the difference between the annual global air temperature and the 1951-1980 mean (average). Thus a positive anomaly means above average temperature, a negative anomaly represents below-average temperature. The warmest years on record have occured since 2000.

Dry Adiabatic Lapse Rate (DALR)

is 1 degree Celsius / 100 m, and can be applied to the cooling of unsaturated air that is rising or the warming of air that is sinking

Adiabatic cooling

the cooling effect of reduced pressure on air as it rises higher in the atmosphere and expands. It is the most important way in which air may be cooled to its dewpoint temperature, causing saturation, condensation, and cloud formation.