OBIS-SEAMAP - help/layer

Layer Selection Overview

For advanced exploration of the OBIS-SEAMAP data, you can overlay pre-defined, commonly referred layers.

There are three types of layers

Species range map
Jurisdictional or biogeographic zoning
Satellite imagery of the environmental data

Species Range Map

The species range map displays the distribution(s) of one or multiple species currently selected in the Species selection panel. Currently distributions are available for some of the marine mammals and sea turtles:

Taxa group	Source	Citation
Marine mammals	IUCN	IUCN 2009. IUCN Red List of Threatened Species. Version 2009.1; http://www.iucnredlist.org
Seabirds	Birdlife International &IUCN	BirdLife International and Handbook of the Birds of the World (2016)
Sea turtles	SWOT	SWOT Report - The State of the World's Sea Turtles, Vol 2., (2006) 49 p.; Nichols WJ (2007) Loggerhead sea turtle (Caretta caretta) 5-year review: summary and evaluation. National Marine Fisheries Service and US Fish and Wildlife Service 65 p
Sharks & Rays	IUCN	IUCN SSC Shark Specialist Group

We are planning to update marine mammal distributions in a near future.

Jurisdictional or Biogeographic Zoning

Layer	Description	Source
EEZ	Exclusive Economic Zone	World EEZ v9, marineregions.org
LME	Large Marine Ecosystems	NOAA
MEOW	Marine Ecosystems	Nature Conservancy
World Database of Protected Areas	Marine protected areas from WDPA	Versoin April 2020, Protected planet

< Overlay Layer >

Turn on the checkbox for the layer you want to overlay.
- The layers are color-coded by zone.
- You can't change the colors.
- Multiple layers can be mapped at the same time.

< Select a zone to filter records >

There are two ways to select a zone and filter the records within the zone.

a. Select one from a list of zones

After the layer is mapped, a list of zones within the layer appears below "Zone selection".
From the list, check on one or multiple zones. Every time a zone is turned on, the map is automatically updated with the selected zone highlighted and the records filtered within the zone.

b. Click a zone on the map

When a zone layer is turned on, [Select] button in the toolbar will become available. Press the button.
Click on a zone on the map. The map is automatically updated with the selected zone highlighted and the records filtered within the zone.

< Upload Layer >

You can also upload your data in shapefile format to the map.

Environmental Data

Sea Surface Temperature (PF51)
Source	AVHRR v5 Sea Surface Temperature
Availability	1982 through 2009
Averaging	Yearly, Monthly, 8 Day
Cell size	0.04 degree
Unit	Degree Celsius
Notes	When the temporal scale is set to "day", an 8 Day average that the selected date belongs to is picked up. Minimum overall quality flag = 4; 2005 yearly data are from the NOAA-17 interim HDF.
Sea Surface Temperature (OISST)
Source	Optimum Interpolation Sea Surface Temperature v2.0
Availability	1981-09-01 through 2019-12-31
Averaging	Daily
Cell size	0.25 degree
Unit	Degree Celsius
Notes	When the temporal scale is set to "day", an 8 Day average that the selected date belongs to is picked up.
Sea Surface Height
Source	Aviso Global DT-Upd Merged MADT SSH
Availability	1992-288 through 2010-090
Averaging	Weekly
Cell size	0.25 degree
Unit	cm
Notes	When the temporal scale is set to "month", a weekly average that the first day of the month belongs to is picked up.
Chlorophyll-a (SeaWiFS etc)
Source	SeaWiFS (SeaStar) / MODIS (Aqua) / CZCS (Nimbus 7) / OCTS (ADEOS-1)
Availability	Jan 2011 = MODIS Sept 1997- Dec 2010 = SeaWiFS Nov 1996 – June 1997 = OCTS Sept 1978 - June 1986 = CZCS
Averaging	Yearly, Monthly, 8 days
Cell size	0.08 degree
Unit	mg*m-3
Notes	Multiple data sources are put together to expand the temporal coverage . When the temporal scale is set to "day", an 8 day average that the selected date belongs to is picked up.
Chlorophyll-a (MODIS)
Source	MODIS (Aqua)
Availability	2002-07-04 through 2019-12-31
Averaging	Monthly, Daily
Cell size	9 km
Unit	mg*m-3
Notes	Multiple data sources are put together. When the temporal scale is set to "day", an 8 day average that the selected date belongs to is picked up.
Bathymetry
Source	S2004 (compilation of GEBCO and Smith/Sandwell)
Availability	-
Averaging	-
Cell size	1 arc-minute
Unit	Meters. Depths represented as positive values.
Notes	Bathymetry is available in the simple statistics chart only. You can't overlay it on the map.

< Overlay Layer >

Turn on the checkbox for the layer you want to overlay.
- The layers are color-coded by pixel value.
- You can't change the colors.
- Multiple layers can be mapped at the same time.
For the layer with a temporal series, you can change the time range. By default, the time range is fixed to 2001-01. See below for more details.

< Time Range >

There are two ways to specify a time range for which the environmental layer is picked up.

a. Specify a particular year/month/day

Choose "Fixed" option.
Enter a particular year/month/day in the textbox with the following format and hit the return key.

Format	Example for May 6th, 2001
M/D/YYYY	05/06/2001 or 5/6/2001
YYYY/M/D	2001/05/06 or 2001/5/6
M-D-YYYY	05-06-2001 or 5-6-2001
YYYY-M-D	2001-05-06 or 2001-5-6
YYYYMMDD	20010506

Day and/or month parts can be dropped. When day or month part is missing, it is intented to get monthly or yearly average of the specified layer, if such average is available.

b. Set a time range using the time series chart

Open the chart panel.
Choose [Time series] if the time series chart is not yet shown.
Adjust the temporal resolution from Year, Year-month, Year-month-day.
- A choice of decade or century is not supported.
Select a chart bar(s) to define the temporal period.
- When a range is selected (e.g. From 2006-05 to 2010-09), the latest period is picked (e.g. 2010-09).
Back to [Time Range] section in the Layer Selection, choose "Selected with Chart" option.
- When "Selected with Chart" is selected while no bar is selected, a warning pops up.