# Oceanography

posted by .

On a sunny day in an estuary, the surface irradiance is 1.6*10^17 photons cm^-2 s^-1. What is k if the irradiance is 7.3*10^13 photons cm^-1 s^-1 at 16 m depth?

At a spot in the ocean, the surface irradiance is 7.8*10^16 photons and k=.14 m^-1. At what depth does the euphotic zone end?

Your airplane leaves 20 degrees N(linear velocity= 845 nm/h) heading to a point due north at 25 degrees north (linear velocity = 815 nm/h). You set the autopilot dor due north and go to sleep. If your flight time is 30 minutes, how far off and in what direction are you if you take no corrective action?

What is the instantaneous acceleration (both magnitude and direction) due to the coriolis force on an object moving at 160 m s^-1 to the west located at 17 degrees south, 86 degrees west?

In a fit of pique, the Canadians fire a cannonball due south from vancouver (lat 49.2 degrees N) at a randomly picked city (39.4 degrees N). Assuming the cannonball takes 48 minutes to get there, by how far and in what direction will the cannonball miss?

• Oceanography (Help please Damon!) -

If you had posted these questions separately, an answer might have been obtained sooner. I can only help with some of your questions. Oceanography is not my field.

(a) For the first one, solve this "Beer's law" equation for k:

exp(-kL) = 7.3*10^13/1.6*10^17 = 4.56*10^-4
kL = 7.7
k = 7.7/16 = 0.48 m^-1

This assumes the sun is overhead. It usually isn't.

(b) Use the same equation, but the lower value of k. Use the definition of the the "euphotic zone" (whatever that is) to solve for L

At extreme depths, Beer's law may not apply because scattering becomes important. You also need to know the elevation angle of the sun.

• Oceanography -

I can only guess that we are talking about the decay constant in I = Io e^-kx

Where for example :
Io = 1.6 * 10^17 *10^4 photons/m^2s
and
i at 16 m = 7.3 * 10^13 * 10^4 = 1.6 * 10^17 * 10^4 * e^-k(16)
4.56 *10^-4 = e^-16k
ln 4.56 -4 ln10 = -16 k
1.517 - 9.210 = -7.693 =16 k
k = 0.481/m

For the second part I do not know how dark it is when we say the euphotic zone ends. I am sure the irradiance for that is defined in whatever text the student is using.

## Similar Questions

1. ### Physics

On a bright sunny day the irradiance on the surface of the ocean is 1.6*10^17 photons cm^-2 s^-1. If k=0.02 m^-1 a) How much light is left (irradiance) at 15 m?
2. ### Physics

At a spot in the ocean, the surface irradiance is 7.8*10^16 photons and k=.14 m^-1. At what depth does the euphotic zone end?
3. ### Physics

On a bright sunny day, the irradiance on the surface of the ocean is 1.6*10^17 photons cm^-2 s^-1. If k=0.02 m^-1 a)How much light is left at 15 m?
4. ### Physics

At a spot in the ocean , the surface irradiance is 7.8*10^16 photons cm^-2 s^-1, and k=0.14 m^-1. At what depth does the euphotic zone end?
5. ### Oceanography

a) Describe the generalized flow in a partially mixed estuary by depth. (ie., what is the flow at the surface, middle, and bottom?
6. ### chem

At noon on a clear day, sunlight reaches the earth\'s surface at Madison, Wisconsin, with an average power of approximately 4.00 kJ·s–1·m–2. If the sunlight consists of photons with an average wavelength of 510.0 nm, how many …
7. ### General Chemistry I

At noon on a clear day, sunlight reaches the earth's surface at Madison, Wisconsin, with an average power of approximately 4.00 kJ·s–1·m–2. If the sunlight consists of photons with an average wavelength of 510.0 nm, how many …
8. ### Chemistry

At noon on a clear day, sunlight reaches the earth\'s surface at Madison, Wisconsin, with an average power of approximately 1.00 kJ·s–1·m–2. If the sunlight consists of photons with an average wavelength of 510.0 nm, how many …
9. ### Chemistry

At noon on a clear day, sunlight reaches the earth\'s surface at Madison, Wisconsin, with an average power of approximately 7.00 kJ·s–1·m–2. If the sunlight consists of photons with an average wavelength of 510.0 nm, how many …
10. ### physics

At noon on a clear day, sunlight reaches the earth\'s surface at Madison, Wisconsin, with an average power of approximately 1.00 kJ·s–1·m–2. If the sunlight consists of photons with an average wavelength of 510.0 nm, how many …

More Similar Questions