MHKiT WPTO Hindcast Example
This example demonstrates how to load and analyze data from the WPTO hindcast dataset hosted on AWS.
Dataset Description
The dataset consists of two main components:
High-spatial-resolution dataset ('3-hour'):
- Covers U.S. Exclusive Economic Zone (EEZ) along West coast and Hawaii
- Uses unstructured grid with ~200m resolution in shallow water
- 3-hour time step resolution
- Spans 32 years (01/01/1979 - 12/31/2010)
Virtual buoy dataset ('1-hour'):
- Available at specific locations within the spatial domain
- Spans same 32-year period
- 1-hour time resolution
Available Variables
3-hour Dataset Variables:
Variables are indexed by latitude, longitude, and time:
- energy_period
- maximum_energy_period
- mean_absolute_period
- mean_zero-crossing_period
- omni-directional_wave_power
- peak_period
- significant_wave_height
- water_depth
- spectral_width
- directionality_coefficient
1-hour Dataset Variables:
Includes all variables from 3-hour dataset plus:
- directional_wave_spectrum
- maximum_energy_direction
- mean_wave_direction
- frequency_bin_edges
Data Access Configuration
To access the WPTO hindcast data:
- Obtain API key from https://developer.nrel.gov/signup/
Example 1: Request Single Location Data
Request 3-hour significant wave height data for 1995 at PacWave South This example demonstrates basic data retrieval for a single parameter at one location
% Set parameters for data request
data_type = '3-hour';
year = 1995;
lat_lon = [44.624076, -124.280097]; % PacWave South
parameter = ["significant_wave_height"]; % Requested parameter
api_key = '3K3JQbjZmWctY0xmIfSYvYgtIcM3CN0cb1Y2w9bf'; % Demo API key (rate-limited)
% Request data for the specified location and time period
wave_data = request_wpto(data_type, parameter, lat_lon, year, api_key);
Plot significant wave height (Hm0) time-series
figure('Position', [100, 100, 1000, 400]);
plot(wave_data.time, wave_data.significant_wave_height, 'LineWidth', 1.5);
title(['Significant Wave Height (Hm0) at ' num2str(wave_data.metadata.latitude) '°N, ' ...
num2str(-1 * wave_data.metadata.longitude) '°W']);
xlabel('Time');
ylabel('Hm0 (m)');
grid on;
xtickformat('MMM-yy');
Example 2: Request Multiple Locations and Parameters
Locations:
Request 3-hour energy period and significant wave height at two locations This example shows how to handle multiple parameters and locations simultaneously
% Define multiple parameters and locations
parameter = ["energy_period", "significant_wave_height"];
lat_lon = [44.624076, -124.280097; % PacWave South
43.489171, -125.152137]; % PacWave North
% Request data for both locations
wave_measurements = request_wpto(data_type, parameter, lat_lon, year, api_key);
Create subplots for energy period and Hm0 at both locations
figure('Position', [100, 100, 1200, 800]);
% Plot Energy Period
subplot(2,1,1);
plot(wave_measurements(1).time, wave_measurements(1).energy_period, '-', 'LineWidth', 1.5);
hold on;
plot(wave_measurements(2).time, wave_measurements(2).energy_period, '--', 'LineWidth', 1.5);
hold off;
title('Energy Period at Two Locations');
xlabel('Time');
ylabel('Energy Period (s)');
grid on;
legend(['Location 1 (' num2str(wave_measurements(1).metadata.latitude) '°N, ' ...
num2str(-1 * wave_measurements(1).metadata.longitude) '°W)'], ...
['Location 2 (' num2str(wave_measurements(2).metadata.latitude) '°N, ' ...
num2str(-1 * wave_measurements(2).metadata.longitude) '°W)']);
xtickformat('MMM-yy');
% Plot Significant Wave Height
subplot(2,1,2);
plot(wave_measurements(1).time, wave_measurements(1).significant_wave_height, '-', 'LineWidth', 1.5);
hold on;
plot(wave_measurements(2).time, wave_measurements(2).significant_wave_height, '--', 'LineWidth', 1.5);
hold off;
title('Significant Wave Height (Hm0) at Two Locations');
xlabel('Time');
ylabel('Hm0 (m)');
grid on;
legend(['Location 1 (' num2str(wave_measurements(1).metadata.latitude) '°N, ' ...
num2str(-1 * wave_measurements(1).metadata.longitude) '°W)'], ...
['Location 2 (' num2str(wave_measurements(2).metadata.latitude) '°N, ' ...
num2str(-1 * wave_measurements(2).metadata.longitude) '°W)']);
xtickformat('MMM-yy');
Example 3: Request High-Resolution 1-Hour Data
Request 1-hour temporal resolution data including directional wave spectrum This example demonstrates working with high-resolution temporal data and spectral information
% Set parameters for 1-hour data request
data_type = '1-hour'; % Using 1-hour dataset
parameter = ["peak_period", "omni-directional_wave_power"];
lat_lon = [44.624076, -124.280097]; % PacWave South
% Request high-resolution data
hourly_wave_data = request_wpto(data_type, parameter, lat_lon, year, api_key);
Plot peak period and omnidirectional wave power
% Peak Period Plot
figure('Position', [100, 100, 1000, 400]);
plot(hourly_wave_data.time, hourly_wave_data.peak_period, 'LineWidth', 1.5);
title(['Peak Period at ' num2str(hourly_wave_data.metadata.latitude) '°N, ' ...
num2str(-1 * hourly_wave_data.metadata.longitude) '°W']);
xlabel('Time');
ylabel('Peak Period (s)');
grid on;
xtickformat('MMM-yy');
% Omnidirectional Wave Power Plot
figure('Position', [100, 100, 1000, 400]);
plot(hourly_wave_data.time, hourly_wave_data.omni_directional_wave_power, 'LineWidth', 1.5);
title(['Omnidirectional Wave Power at ' num2str(hourly_wave_data.metadata.latitude) '°N, ' ...
num2str(-1 * hourly_wave_data.metadata.longitude) '°W']);
xlabel('Time');
ylabel('Wave Power (kW/m)');
grid on;
xtickformat('MMM-yy');
