hi-resolution local ecological marine units6.31 12.56 18.8 25.05 37.51 50.03 31.29 43.78 56.27 62.52...
TRANSCRIPT
SELECT
DownloadnetCDF files by variableby dataset
GenerateCharts
Symbolize
Summarize
Generate3D Point Mesh
ConvertNet CDFs toSingle CSV filesby dataset
Variable DatasetCSV
Import CSVas table tofGDB
Convert dateto standardformat
JAN
Make XYEvent Layer
Define LocalCoordinateSystem
Feature Class toFeature Class
Piecewise 3DInterpolation(each variable)
3D Visualization,Summary Plotsand Tables
Local EMUs
LocalizedEMUClusters
0
-1,000
-2,000
-3,000
-4,000
4 8 12 16 20 24
Dep
th
Temperature
Scatter Plot of Temperature by Depth
R2 = 0.76
A 250 square kilometer grid with 5,518 points
Counts of EMUs within the Study Area
Top 3 Prominent EMUs
Number of ObservationsTemperature: 4,983,203
Salinity: 2,953,802
Oxygen 96,824
30
200176
820
33 10
337 273
568
350
400
600
800
6 10 13 19 26 33 36 37
Co
unt
EMU Number0 13 1
EMU N
37 250500555500555050
NumberN
5
1N
7 84
99 26N bN
3
5
3
19N
7 8484
56855
100
568
3 33
56
33
56
1111100
3
64
36 37
0000000000000000000000000000000 646446446464664
Clustering resulted in 8 prominent clusters representing over 98% of the sample. Cluster 17 and 1 make up the majority of surficial waters.
The distinct surficial water masses are merging around Point Conception, and this is noticeable. The cooler water from the north is colliding with the southern waters and mixing in this region.
1
2 4
53
Create point mesh4
Populate point mesh with seasonal data by interpolating to a 3D mesh using the Linear Interpolation Method
5
Cluster using the 12 attributes6
Results
8
0
-1,000
-2,000
2 4 6 8 10 12 14 16
Distribution of attribute values
Scatter Plot of Temperature by Depth
R2 = 0.52
Plot of Temperature by Time
200,000
400,000
600,000
01896(2/1)
2016(2/1)
1916 1936 1956 1976 1996
Distribution of attribute values
Collection Date
Histogram of Temperature Values
MeanMedian
Standard Deviation1,000,000
2,000,000
3,000,000
0
6.3112.56
18.825.05 37.51 50.03
31.29 43.78 56.2762.52
68.7675.01
81.2587.5
99.99
93.740.07
Distribution of attribute values Temperature
Temperature
Use charts to help identify and remove outliers
Create charts for each one of the datasets1
2 Use convert time field to add months as an attribute to the table (converted from Date)
Oxygen Measurements by Month
10,000
20,000
30,000
01 2 3 4 5 6 7 8 9 10 11 12
Month
Salinity Measurements by Month
100,000200,000300,000400,000
01 2 3 4 5 6 7 8 9 10 11 12
Month
Temperature Measurements by Month
200,000
400,000
600,000
800,000
01 2 3 4 5 6 7 8 9 10 11 12
Tem
per
atur
eSa
linity
Oxy
gen
Month
3
Dec
Nov
Oct
Sep
Aug
Jul Jun
May
Ap
r
Mar
Feb
Jan
Temperature observations by month for past 10 years
0 - 426
2017201620152014201320122011201020092008
426 - 1,4941,494 - 3,2403,240 - 6,8426,842 - 16,163
Histogram of Temperature Values50,000
40,000
30,000
20,000
MeanMedian
Standard Deviation
10,000
0
2.424.35
6.278.19 12.04 15.89
10.12 13.96 17.8119.73
21.6523.58
25.527.42 31.27
29.350.5
Co
unt
Temperature
25 m
100 m Surface Area
Volume
Thickness
Unit Bottom
Unit Top
UnitMIddle
100 m5500 m
0 m
5500 m
0 m
10 m
5 m
EMU 3D Point MeshFramework
World Ocean Atlas EMU Points Feature Attributes
Depth LevelTemperatureSalinityDissolved OxygenNitrateSilicatePhosphate
MODIS ocean color
GeomorphologyBaseGeomorphologyFeaturesSurfaceAreaVolume, SpecialCases
PointIDQuarterIDUnitTop (m)UnitMiddle (m)UnitBottom (m)Thickness (m)ThicknessPos (m)EMUIDEMU Name
19
18
8
21 24
11
926
10
33
29
3 36
37
1413
5
2325
303135
00
Surface Area (km2)
Dep
th (m
)
AB
YSS
OPE
LAG
ICB
ATH
YPE
LAG
ICM
ESO
PELA
GIC
EPIP
ELA
GIC
100million
200million
300million
200
400
600
800
1000
1200
1400
1600
1800
2000
3000
4000
5000
5500
Hi-Resolution Local Ecological Marine UnitsA workflow for generating a three dimensional mapping of the ocean
WorkflowWhy? FINDINGS: Hawaii
FINDINGS:
Santa Barbara
Sayre, R.G., Wright, D.J., Breyer, S.P., Butler, K.A, Van Graafeiland, K., et al., 2017. Oceanography, 30(1), doi:10.5670/oceanog.2017.116
To maintain a healthy ocean and support sustainability, it is necessary to have a baseline for understanding the ocean’s ecosystems and a framework for detecting change.
In support of that goal, Sayre et al. (2017) developed a three-dimensional mapping of the oceans based on physiochemical environmental data and created a database of over 52 million points that depict the global ocean in x, y, and z dimensions. These points were clustered into 37 distinct volumetric region units, called ecological marine units (EMUs).
The horizontal resolution of the EMU mesh is a ¼° x ¼° grid (~27 km2 at the equator). In the vertical dimension, mesh points are located at variable depth intervals, ranging from 5 m increments near the surface to 100 m increments at depth. A total of 102 depth zones extend to 5,500 m.
While the EMUs have proven useful in a variety of global scale analyses, Sayre et al. recognize their limitations at other spatial scales stating, “global analyses are useful for macroscale comparisons of ocean regions, local management strategies and policies will require appropriately scaled geographic assessment and accounting units” (p. 91).
This poster describes a workflow that addresses the scalability issues of the global EMU dataset. The workflow shows how to build, visualize, analyze and share highly localized EMUs using data from both NOAA’s World Ocean Database and your local in situ observations.
In this example, the grid is not dense enough, and we want to cluster with seasonality.
Project coodinate system:
UTM Zone 10N
Number of global EMU’s within the Study Area: 57
Number of different EMU classifications: 9
Shallow, Cool, Normal Salinity, Moderate Oxygen, Medium Nitrate, Low Phosphate, Low Silicate
Moderate Depth, Very Cold, Normal Salinity, Very Low Oxygen, High Nitrate, Medium Phosphate, Medium Silicate
Moderate Depth, Cold, Normal Salinity, Very Low Oxygen, High Nitrate, Low Phosphate, Low Silicate
Use a definition query on the data to select seasons: https://www.timeanddate.com/calendar/aboutseasons.html
SQL Query = Sample_Month IN (3, 4, 5) for SpringSQL Query = Sample_Month IN (6, 7, 8) for SummerSQL Query = Sample_Month IN (9, 10, 11) for FallSQL Query = Sample_Month IN (12, 1, 2) for Winter
3 values: Temperature, Salinity, Oxygen, by 4 Seasons
These observations were taken at depths ranging from the surface to 4,572 meters between the years of 1928 and 2017. Nearly a century of data!
In this example we used the workflow to help understand Oxygen (203) Temperature (228,475) and Salinity (80,227)observations
Project coodinate system: UTM Zone 5N
Number of global EMU’s within the Study Area: 16
Number of different EMU classifications: 9
Data were obtained from the NOAA World Ocean Database through NOAA Select. In this workflow individual netCDF files are converted to a single feature class with attributes representing the sampled variable. Depth information is also translated to corresponding z values in the feature class.
We were also able to incorporate elevation (depth) data from NOAA's Coastal relief modeling to help derive the depths used to create a uniform 3D point Mesh.
https://www.ngdc.noaa.gov/mggcoastal/crm.html Volume 10- Hawaii
This particular point mesh has a 25 square kilometer horizontal cell size (user specified) using the WOA Standard (Oceanic) depth convention (also user specified) and is comprised of 164,019 points from the surface to 3,900 meters in depth
Data can be symbolized using Cluster ID
Now the temperature, salinity, and oxygen observations can be used to interpolate those values to the 3D point mesh.
Once the values are interpolated to the 3D Point Mesh, clustering can be used to group the data based on attribute values.
In this scenario the software decides the appropriate number of clusters (after data valuation). From here a table and supporting graphics can be generated showing the clustering results.
In this example we classified based on temperature, oxygen and salinity. 29 clusters were determined.
How?The EMU data set is an open-access resource available in both open data (e.g. an OGC geopackage) and standard commercial GIS formats (Esri file geodatabase).
We present a set of preconfigured steps which encapsulate a GIS workflow , a form of guided data analysis, which yields local EMUs.
The guided data analysis is flexible and provides measures that promote quality assurance and customization along the way.
Link to Project and Workflow: http://esriurl.com/LocalEMU
1 x 1 degree area off the west coast of Hawaii.
3 x 2 degree area off the coast of Southern California.
The Process
Data values are in Celsius. There are some apparent outliers that are identifiable in the graph and can be removed prior to clustering. You have the ability to trace these outliers back to the source dataset.
This graph shows the distribution of depth values associated with temperature. Most values are found between 0 and 1,400 meters. You have the ability to interact with the data and identify which values in the graph correspond with the spatial locations in the map.
This shows that there is a huge history of data here. It might be best to focus or work with the most recent data, collected within the last 30 years?