ba·thym·e·try (n.)  - The measurement of the depth of bodies of water.


NEW 2009 - Google Earth Renderings!

Introduction:

I've always had a fascination with maps, charts, aerial photos, and even flying because it gives me the power to see and understand the world in a much larger way.  My diving hobby has recently prompted me to get more serious about mapping and take a more powerful approach to the problem of understanding my local underwater topography.  My goal for learning GIS is to get a better understanding of my local underwater environment and to find new and interesting SCUBA diving sites.  Although I'm very much a novice at this, I've have lots of fun processing the data and correlating what I see in the data to what I see on my dives. 

The tool used by professionals to manage geographic data is known as a Geographic Information System or GIS.  There are dozens of GIS packages ranging from the free MicroDEM to the industry standard $3K-$6K ESRI ArcGIS.  A smaller and more forward-thinking company in the GIS arena is Manifold.  After consulting with several GIS experts, I decided to adopt the modestly priced, yet technically impressive, Manifold GIS System for my research.

From my neophyte point of view, there are 3 parts to the mapping equation - (1) the GIS package, (2) data, and (3) precisely knowing your location.  Manifold handles #1 nicely.  The internet has evolved to the point where there are vast quantities of GIS data available for free download.  In fact, there is so much data out there that finding what you want can be the hardest part.  Knowing your location easier than ever before since there are now WAAS handheld GPS units that can measure your position to within 3m 95% of the time!

This page in an on-line "lab notebook" of sorts.  Since this is just a hobby I don't put enough effort into any of these to make them publication quality.  I usually just play with them until I think they look pretty or friends agree that they are cool or useful.  I'm always looking for constructive ideas to improve my maps and I'm especially in the market for better data.  Please contact me if you have anything to add!

Here are a few maps that I've made:


 
Farnsworth Bank Divers Map

This is my latest work on Farnsworth Bank. 
Click here to go to my Farnsworth Bank page.

 

Redondo Canyon Divers Map

Redondo Canyon, aka "Vets Park" is one of the most popular local dive spot.  It offers great exploration of the submarine canyon and is also favorite location for dive instruction.  The availability of parking, restrooms, showers, steps down to the beach, and a sand entry make it one of the easiest places to dive in Southern California.  Although it's a good beginners spot, the canyon is rich with opportunity to see unusual critters for even the most seasoned diver.  It's especially thrilling to dive at night. 
Link to my Vets pics.
 


 
Old Marineland Divers Map

My buddy Phil Garner recently discovered what he believes to be the remains of an old Pier at the Old Marineland Dive Site.  I think this map correctly identifies the structure on the data.  We're still not sure what we're looking at since the pier shouldn't be out this far according to the post card image.  Maybe it was towed out and sank?

 


 
Christmas Tree Cover Divers Map

Christmas Tree Cove is one of my favorite dive sites.  Although I've dove it nearly a dozen times, I never had a clear picture of the reef layout in my mind.  There are so many wonderful little walls, pinnacles and overhangs that it's easy to get turned around.  This is still in draft stage as I need to add more annotations & coords.

Shorediving.com information on Christmas Tree Cove
 


 
Neptune Cove to Christmas Tree Cove Divers Map

There are two amazing dives to be had at Neptune.  The first is to swim to the South West and dive the pinnacles visible near the bottom of the map.  The other is to attempt the Neptune - Christmas Tree Traverse.  Taking the most optimal route, this is a 1000m swim from entry to exit.  With single tanks, we usually run low on air at about the reef on the South end of Christmas Tree Cove.  The dive turns out to be about 90-100 minutes of bottom time at a depth of 20-40 ft.  You typically want to go Neptune-Xmas because the hill climb at Christmas Tree cove is easier.
 


 
La Jolla Canyon Divers Map

La Jolla Canyon Divers Map Rev 1.pdf - Higher detail and optimized to print on legal paper


 
Scripps Canyon Divers Map

Scripps Canyon Divers Map Rev 1.pdf - Higher detail and optimized to print on legal paper


 

Southern California Offshore SCUBA Destinations

11 Islands, 4 Banks, 3 Rocks, and a serious Pinnacle!  We're  fortunate to have such incredible places to explore here in SoCal!

The base image is from MODIS Rapid Response Team.  Locations for various banks and pinnacles were transferred from NOAA Nav Charts that had also been imported into Manifold.  It was finished up with Photoshop for color correction, labels, north arrow, etc. 
Alternate version  by Jeff Shaw.
 


 
Dirty run-off from the massive rains of early 2005.

Image courtesy of MODIS Rapid Response Team.  This image was taken on Jan 12, 2005 two days after the terrible La Conchita Landslide.  It was speculated by many of us that the excessive run-off would fuel a terrible bout of red tide and poor visibility over summer 2005 as the water began to warm up.   We're not sure about the science of this theory but as July 2005, after suffering with months of red tide, it seems reasonable.


 
Catalina Island Isthmus

This one is still under construction.
 It looks pretty nifty so I'm putting a copy here for others to enjoy until I have time to improve it.


Catalina Isthmus Reserve & Surrounding Area Rev1.pdf

 

 
Pt Sur Bank

I've done some rough work on Pt Sur Bank to assist Dr. Bob Schmeider in his research of the area.  Nothing fancy, just some bathymetry maps with screen shots of the areas that we dove.
Click here to go to my Schmeider Bank page.

 


Data Sources -
multibeam sonar surveys, charts, coastlines, images, etc:

http://pubs.usgs.gov/of/2004/1221/ - USGS Los Angeles Margin Map (4m bathy & backscatter), result of a FOIA request!

http://walrus.wr.usgs.gov/pacmaps/la-index.html - USGS Los Angeles Margin Map (16m bathy & backscatter)

http://pubs.usgs.gov/of/2003/of03-320/index.htm - USGS Lake Mead Data.  Can you find the B-29?

http://geopubs.wr.usgs.gov/open-file/of03-85/4_catalog.html - USGS California Coastline Map (amazing resolution)

http://seafloor.csumb.edu/SFMLwebDATA.htm -  Various amazingly high res data.  See Catalina Isthmus, Santa Monica, & PV

http://historicals.ncd.noaa.gov/historicals/histmap.asp - Historical Nav Charts in MrSid format, search region=CA, type=Nav Chart

http://rapidfire.sci.gsfc.nasa.gov/subsets/?AERONET_La_Jolla/ - Almost Real Time Satellite Image of Southwest US & Baja, updated daily!

http://photojournal.jpl.nasa.gov/catalog/PIA03372 - Amazing Landsat Photo of SoCal, it's a shame its not georegistered

http://seamless.usgs.gov/website/seamless/viewer.php - Most of the source data for TerraServer & Google Earth in GIS ready format
 

Data Sources - locations of things:

Between Two and Twenty Fathoms Book - an incredible source of local knowledge by Captain Mark Wisch, ~320 accurate waypoints!

http://mysite.verizon.net/jeffspira/hp_wrec.html - Jeff Spira's Shipwreck database for Southern California (mostly from AWOIS)

http://chartmaker.ncd.noaa.gov/hsd/hsd-3.html - AWOIS - Automated Wreck and Obstruction Information System

http://www.dfg.ca.gov/mrd/artificialreefs/ - CA DFG Artificial Reef Database

http://www.mms.gov/omm/pacific/lease/decom.htm - Locations of all SoCal Offshore Oil Platforms (see proceedings p234)

 

Misc Resources and Software Packages:

http://www.decompression.org/maiken/IsthmusDeep.htm - Eric Maiken has some great rendering of Catalina's Isthmus Deep Reef

http://www.manifold.net - An excellent GIS package and a steal at twice the price!

http://www.3dnature.com/tutorials/NLCD/NLCD4_body.htm - info on modifying the metatags in GeoTIFFs

http://ioc.unesco.org/oceanteacher/resourcekit/M3/Toolbox/GeoTIFFExaminer.htm - quick peek into GeoTIFF tags

http://www.gpstm.com/ - Excellent for transferring files between various GIS programs and GPS units

http://jdmcox.com/ - USA Photomaps, rips space shots from TerraServer and allows GPS waypoint/tracklog overlay.

 

GPS Resources:

http://gpsinformation.net/ - Like it says, GPS information!

http://www.kh-gps.de/nmea-faq.htm - Great article on NMEA decoding if you're rolling your own

http://www.confluence.org/index.php - Just plain cool

http://williams.best.vwh.net/gccalc.htm - Great circle calculator, find new location given bearing + distance, etc

http://www.geocode.com/modules.php?name=TestDrive_Eagle - Geocoder (lat/long given address) 

 

 


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