Reefquest

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The primary page for the [|Reefquest] project.

Project 2 - Overlaying temperature data onto maps and comparing inferred current data, as well as temperature data, to visual checks of the health of the reef site.

Resources on visually checking the health of the reef: 1. Coral Health color card: 2. Cards on expected and invasive species in Hawaiian reefs, as well as how to identify various reef illnesses: 3. An overview of the Kahekili reef near Lahaina, Maui: 4. ReefQuest Kahekili Reef Dead Zones Visualization: 5. ReefQuest Kahekili Reef Fisheries Management Area:

Project 1 - Inferring current data from temperature data taken at Lahaina, Maui in August 2012. Purpose: The purpose of this project is to find out where pollution is coming from, using turbidity and current patters. Background research on tracing runoff in Lahaina.

Overview: To find where pollution is coming from we first must find how many pollutant particles are in the water. We will do this by finding the turbidity of the water with light sensors. Once the turbidity is known we can use current as a function of time to figure out where the pollution is coming from. (The pollution is most likely waste products from resorts.)

Our current project with Reefquest involves the logging of data at five sensor sites at a reef site immediately off of the coast of Maui.


 * 1) Measured data (Note: All of the data can be stored as a vector, with the exception of surface light intensity and time, which are scalars. Temperature, depth, light intensity, current velocity, and absorption coefficients are all time dependent.).
 * Measure Value || Description || Units || Measurement frequency || Variable ||
 * Water temperature || Water temperature measured at depth || degrees Celsius || Every minute || T_i = {T_1, T_2, T_3, T_4, T_5} ||
 * Time || Absolute clock time || seconds || Every minute || t ||
 * Surface light intensity || Light intensity measured at one point for the surface of the reef || lux || Every minute || I_0 ||
 * Initial depth || The depth of each sensor at the time of their placement. The time of placement needs to be recorded || meters || Once || D_i = {D_1, D_2, D_3, D_4, D_5} ||
 * Sensor positions || The gps coordinates of each sensor || degrees || Once || (X_i,Y_i) i=1,5 ||

Calculated data X_i X_j Y_i Y_j ||  || X_j Y_i Y_j ||  || Step 2: V_ij = r_ij / delta-t || T_i r_ij t ||  || t Tide charts || [|Tidal depth for Lahaina, Maui] || I_i(t) I_0 ||  || T_noon T_sunset T_sunrise ||  ||
 * Calculated value || Variable || Units || Variable Formula || Inputs || Source Data ||
 * Distance between two sensor sites || r_ij || meters || r_ij = 2*R*arcsin(sqrt[sin^2(0.5*(X_i-X_j))+cos(X_i)*cos(X_j)*sin^2(0.5*(Y_i-Y_j))] || R = radius of the Earth = 6378100 meters
 * The angle from sensor site i to j || theta_ij || degrees || theta_ij = arctan^2([cos(X_i)*sin(X_j)-sin(X_i)*cos(X_j)*cos(X_j-X_i)]/[sin(Y_j-Y_i)*cos(X_j)]) || X_i
 * The current speed from sensor site i to j || V_ij || meters per second || Step 1: Water temperature versus time is plotted to produce five graphs. Similar features between two graphs, say T_1 and T_2, are used to determine the difference in time, delta-T, between two similar peaks or troughs in temperature. This yields a delta-t between those two graphs at a particular interval, and is then used to determine the current speed during that same interval.
 * The depth of the sensor as a function of time || D_i(t) || meters || D_i(t) = D_i + h(t), where h(t) is the change in tidal depth from the time of initial placement. || D_i
 * The absorption coefficient || a_i(t) || Inverse meters || a_i(t) = (-1/D_i(t))*ln(I_i(t)/I_0) || D_i(t)
 * Tilt angle for each sensor || theta || Radians || [[image:Tilt angle.png]] || T_brightest

theta ||  || T_sunrise T_sunset ||  || alpha ||  || I_w I_b || [|Astronomical correction data] || s a b || [|Astronomical correction data] || phi_A (represented by phi) z || [|Astronomical correction data] ||
 * Calculated value || Variable || Units || Variable Formula || Inputs || Source Data ||
 * Corrected lux || I_A || lux || [[image:Corrected lux.png]] || I_0
 * Angle of the Sun || phi_A || Radians || [[image:Angle of the sun.png]] || T_current
 * Albedo || alpha ||  || [[image:Screen shot 2012-11-28 at 2.12.46 PM.png]] || theta || [|Astronomical correction data] ||
 * Boundary Intensity || I_b || lux || [[image:Boundry Intencity.png]] || I_A
 * Absorption || a(t) || Inverse meters || [[image:absorption.png]] || D_i(t)
 * Overall tilt angle || theta || Radians || [[image:Overall tilt angle.png]] || z
 * Azimuth || a || Radians || [[image:Azimith.png]] || delta
 * Zenith || z || Radians || [[image:Zenith.png]] || phi_A (represented by phi)

delta omega || [|Astronomical correction data] || Data from the August 2012 session in Lahaina, Maui:
 * Angle of the sun relative to normal || Omega || Radians || [[image:Angle of the sun relitive to normal.png]] || phi_A || [|Astronomical correction data] ||
 * Declination || delta || Radians || [[image:Declination.png]] || N || [|Astronomical correction data] ||