Transportation & Safety

NOAA Operational ACSPO SST L3S Day/Night AM/PM product suite

michael.soracco — Tue, 01 Oct 2024 17:06:27 +0000

NOAA Operational ACSPO SST L3S Day/Night AM/PM product suite michael.soracco Tue, 10/01/2024 - 13:06

Date

October 1, 2024

Category

Announcement

Author(s)

msoracco

Data Applications

Climate & Weather

Ecosystem Monitoring

Fisheries & Aquaculture

Ocean & Coastal Dynamics

Transportation & Safety

Water Quality

NOAA CoastWatch has added the operational SST L3S Day/Night AM/PM product suite to HTTPS distribution:

https://coastwatch.noaa.gov/data/pub0053/coastwatch/sst/l3s/

The morning/afternoon orbit, day and night SST L3S products are now produced by the Office of Satellite and Product Operations. Products are mirrored daily and have increased reliability. Fifteen (15) days of operational near real-time data are available in this directory. Note, the L3S Daily product is not currently produced by OSPO. A transition from research (STAR) to operational (OSPO) processing is expected to begin at the end of 2024.

At present the L3S produced within OSPO uses ACSPO version 2.8x. Sea surface temperature data differences with the STAR produced L3S (ACSPO v 2.8x+) are considered negligible.

New experimental mesoscale eddy products

michael.soracco — Tue, 03 Sep 2024 12:26:27 +0000

New experimental mesoscale eddy products michael.soracco Tue, 09/03/2024 - 08:26

Date

September 3, 2024

Category

Announcement

Author(s)

msoracco

Data Applications

Climate & Weather

Ecosystem Monitoring

Fisheries & Aquaculture

Ocean & Coastal Dynamics

Transportation & Safety

The sea surface height team in NOAA’s Laboratory for Satellite Altimetry developed two experimental mesoscale eddy products:

Multiparameter Eddy Significance Index (MESI)
MUltiparameter NRT System for Tracking Eddies Retroactively (MUNSTER)

MESI serves as a first look indicator of the potential impact a given mesoscale eddy may have on upper ocean dynamics, with potential implications for nutrient cycling, mixed layer dynamics, and fisheries. The MUNSTER suite of eddy tracking products provides analyzed mesoscale eddy properties, contours, and trajectories based on NOAA RADS gridded altimetry and includes analysis calculated from altimetry, SST, SSS, and chlorophyll-a from ocean color. MUNSTER is a threshold free product suite, with no limitations imposed on eddy lifetime or amplitude, and includes a wide variety of analyzed variables, including MESI. The MUNSTER mesoscale eddy product suite has a wide variety of applications across oceanography, including coral reef resilience monitoring, studies of air-sea interactions, harmful algal blooms, coral reef larva dispersion, and fisheries management, among many others.

NOAA CoastWatch has processed a limited number of products that are available for comment through September 30, 2024. Collected feedback and additional enhancements (metadata) will be implemented prior to making a data asset spanning August 2019 to present. Please visit https://coastwatch.noaa.gov/cwn/products/experimental-eddy-products.html to explore these data products and submit feedback to coastwatch.info@noaa.gov.

Hardware issues result in inaccessible data

michael.soracco — Mon, 26 Aug 2024 12:34:22 +0000

Hardware issues result in inaccessible data michael.soracco Mon, 08/26/2024 - 08:34

Date

August 26, 2024

Category

Announcement

Author(s)

M Soracco

Data Applications

Climate & Weather

Ecosystem Monitoring

Fisheries & Aquaculture

Ocean & Coastal Dynamics

Transportation & Safety

Water Quality

Update (20240826 - 1600Z) : Data access has been restored.

Over the weekend (24 August 2024) a hardware issue resurfaced causing a '403 Forbidden' error to be given by the webserver when attempting to access select data.

Data affected include:

ACSPO SST L3S [including L2P and L3U],
Blended Geo-Polar 5km SST,
VIIRS Level-2 Ocean Color data,
Chlorophyll-a DINEOF,
VIIRS Science Quality Data - Daily, Weekly, Monthly
Altimetry [rads] Sea Level Anomaly,
Geostrophic currents,
East Coast Node SST,
Blended Winds (6hr, Daily)
Sentinel-2 MSI L1C data
Ocean Heat Content

Data paths affected include those containing 'pub0010 or socd1', 'pub0012 or socd2', 'pub0014 or socd4', and 'pub0015 or socd5.' Work is underway to resolve the issue. At this point the status of data recovery has not been assessed.

Sea surface temperature processing issues

michael.soracco — Thu, 15 Aug 2024 16:14:37 +0000

Sea surface temperature processing issues michael.soracco Thu, 08/15/2024 - 12:14

Date

August 15, 2024

Category

Announcement

Author(s)

msoracco

Data Applications

Climate & Weather

Ecosystem Monitoring

Fisheries & Aquaculture

Ocean & Coastal Dynamics

Transportation & Safety

Water Quality

Sea surface temperature processing of ACSPO FRAC L2P/L3U and L3S products has been suspended due to ongoing maintenance beginning August 12, 2024. We are hopeful processing is restored today (August 15, 2024) and expect L2P/L3U products to catch-up within 10 hours and L3S in about 24 hours. The global 2km low earth orbit (LEO) Level-3 Supercollated (L3S) product is expected to become operational (24hour-by-7day support) within NOAA NESDIS later this month.

New Hurricane Tool in Development

v.wegman — Fri, 13 Oct 2023 20:05:19 +0000

New Hurricane Tool in Development v.wegman Fri, 10/13/2023 - 16:05

Date

October 13, 2023

Category

Announcement

Data Applications

Climate & Weather

Ecosystem Monitoring

Ocean & Coastal Dynamics

Transportation & Safety

AOML, CIMAS, and CoastWatch have developed an initial version of a hurricane-ocean database and display for all Atlantic tropical cyclones during 2003-2022. The main purpose is to aid hurricane-ocean research by making it easier to view and download storm-specific data, including satellite SST, SSS, sea level, rainfall, winds, ocean color; most in-situ ocean observations; and NOAA aircraft measurements. We invite you to explore it and provide feedback: https://www.aoml.noaa.gov/phod/hurricane_tracker/.

The team have set aside time on Monday, October 23 at 10-11 am ET to provide an overview of the tool, answer questions, and receive any additional feedback.

Google Meet joining info:
Video call link: https://meet.google.com/vyw-ocqc-osm
Or dial: ‪(US) +1 402-726-1148‬ PIN: ‪486 961 676‬#
More phone numbers: https://tel.meet/vyw-ocqc-osm?pin=5901166906104

If you have any questions or would like to provide written feedback, please direct that to Gustavo Goni (gustavo.goni@noaa.gov) and Greg Foltz (gregory.foltz@noaa.gov).

Upcoming ACSPO SST Filename change

michael.soracco — Tue, 12 Sep 2023 14:17:12 +0000

Upcoming ACSPO SST Filename change michael.soracco Tue, 09/12/2023 - 10:17

Date

September 12, 2023

Category

Announcement

Author(s)

msoracco

Data Applications

Climate & Weather

Ecosystem Monitoring

Fisheries & Aquaculture

Ocean & Coastal Dynamics

Transportation & Safety

Water Quality

The NOAA Advanced Clear-Sky Processor for Ocean (ACSPO) L3S-LEO-PM and L3S-LEO-DY products will be updated from ACSPO v2.80 to ACSPO v2.81 on October 2, 2023.

The updates from V2.80 are:

N21 VIIRS has been added to L3S-LEO-PM. Now it includes 3 VIIRS sensors from NPP, N20 and N21
The L3S-LEO-PM daytime SST has been de-trended to fix a ~0.15 K negative drift in bias over the past decade or so.
Aqua MODIS SST has been included in L3S-LEO-PM. This update extends the L3S-LEO-PM dataset back to 4 Jul 2002 when the first Aqua SST became available. Due to current drift of the Aqua satellite orbit, Aqua SST is not included in L3S-LEO-PM after 31 Dec 2022.
Aqua and Terra MODIS SSTs have been both included in L3S-LEO-DY. This extends the L3S-LEO-DY dataset back to 24 Feb 2000, when the first Terra SST became available. Due to current drift of the Terra satellite orbit, Terra SST is not included in L3S-LEO-DY after Dec 31 2021.

Routine users will need to plan for the change in filenames where the version number will change from v2.80 to v2.81.

For example:

from: 20230911120000-STAR-L3S_GHRSST-SSTsubskin-LEO_PM_N-ACSPO_V2.80-v02.0-fv01.0.nc
to: 20230911120000-STAR-L3S_GHRSST-SSTsubskin-LEO_PM_N-ACSPO_V2.81-v02.0-fv01.0nc

Currently the V2.81 NRT data are pushed to
[links invalid after publishing date]
https://coastwatch.noaa.gov/pub/socd2/coastwatch/sst/nrt/l3s/leo/pm_v2…
https://coastwatch.noaa.gov/pub/socd2/coastwatch/sst/nrt/l3s/leo/daily_…

and reprocessed data are pushed to
[links invalid after publishing date]
https://coastwatch.noaa.gov/pub/socd2/coastwatch/sst/ran/l3s/leo/pm_v2…
https://coastwatch.noaa.gov/pub/socd2/coastwatch/sst/ran/l3s/leo/daily_…

We plan to promote V2.81 data on October 2, 2023 to replace the "live" data flow at

https://coastwatch.noaa.gov/pub/socd2/coastwatch/sst/nrt/l3s/leo/pm/
https://coastwatch.noaa.gov/pub/socd2/coastwatch/sst/nrt/l3s/leo/daily/

NOAA-21 reaches Provisional Maturity for SST

michael.soracco — Tue, 12 Sep 2023 13:26:47 +0000

NOAA-21 reaches Provisional Maturity for SST michael.soracco Tue, 09/12/2023 - 09:26

Date

September 12, 2023

Category

Announcement

Author(s)

msoracco

Data Applications

Climate & Weather

Ecosystem Monitoring

Fisheries & Aquaculture

Ocean & Coastal Dynamics

Transportation & Safety

Water Quality

The Joint Polar Satellite System (JPSS) has approved NOAA-21 Visible Infrared Imaging Radiometer Suite (VIIRS) Advanced Clear Sky Processor for Ocean (ACSPO) sea surface temperature (SST) products for Provisional Maturity. This means the product is ready for operational use though incremental improvements and validation will continue as the product moves to Full/Validated Maturity. Learn more about maturity levels

Congratulations to the NOAA Satellites STAR SST Team on reaching this milestone. Explore these products on the CoastWatch SST webpages and services.

Sargassum FAQ

v.wegman — Tue, 04 Apr 2023 22:49:07 +0000

Sargassum FAQ v.wegman Tue, 04/04/2023 - 18:49

Date

April 4, 2023

Category

User Story

Data Applications

Ecosystem Monitoring

Transportation & Safety

Water Quality

The Caribbean overcame significant challenges in 2022 as Sargassum washed ashore in unprecedented amounts. More about that event can be found in a CoastWatch User Story here.

The challenge has since extended to the contiguous United States as the Great Atlantic Sargassum Belt drifts towards Florida. As more people encounter this nuanced macroalgae, it is ever-so important to track, study, and communicate effectively.

A Frequently Asked Questions (FAQs) for Sargassum was composed by the NOAA Atlantic Oceanographic & Meteorological Laboratory (AOML) in partnership with NOAA CoastWatch Caribbean, Gulf of America and Atlantic OceanWatch Node. With permission, we reprint the FAQs here for expedience. Please visit the AOML-hosted Sargassum FAQ page for additional context on Sargassum research, tracking and monitoring. CoastWatch stakeholders may also be interested in the Experimental Weekly Sargassum Inundation Reports.

A mat of free-floating Sargassum found in the Sargasso Sea. Image Credit: University of Southern Mississippi Gulf Coast Research Laboratory

General Sargassum Information

What is Sargassum?

Sargassum is a type of floating brown algae, commonly called “seaweed.” These algae float at the sea surface, never attach to the sea floor, and they can aggregate to form large mats in the open ocean.

Where does it come from?

Historically, the majority of Sargassum aggregated in the Sargasso Sea in the western North Atlantic, with some small amounts found within the Gulf of America and Caribbean Sea. In 2011, the geographic range expanded, and massive amounts of Sargassum moved west into the Caribbean Sea, Gulf of America , and south tropical Atlantic, washing ashore in Florida, Puerto Rico, the US Virgin Islands, and most islands and coastal areas in the Caribbean Sea.

Why did the geographic range for Sargassum expand in 2011?

Researchers are still assessing various hypotheses about the cause of this first documented extreme event. One hypothesis proposes that during the winter of 2009–2010, the winds that typically blow to the east, from the Americas to Europe, strengthened and shifted to the south more dramatically and persistently than any other time in the 1900–2020 record. This shift in winds triggered a long-distance eastward dispersal of Sargassum, from the Sargasso Sea, toward the Iberian Peninsula in Europe and West Africa. After exiting the Sargasso Sea, the Sargassum drifted southward in the Canary Current and entered the tropics. Once in this new and favorable tropical Atlantic habitat, with ample sunlight, warm waters, and nutrient availability, the Sargassum flourished and has continued to grow.
In addition to changing wind patterns, other hypotheses include a combination of factors, such as the variation in the outflow of major rivers (e.g. Amazon and Orinoco), nutrient (nitrogen and phosphorus) concentration in the oceans, increase in the amount of phosphorus due to saharan dust, water temperature, and river runoffs.
Having established a new population, the Sargassum now aggregates almost every year, starting in January/February in a massive windrow or “belt” north of the Equator, along the region where the trade winds converge. During the late winter and early spring months, the Sargassum moves northward with the seasonal winds and currents. By June, this belt may stretch across the entire central tropical Atlantic. Large portions of this algae are then transported into the Caribbean Sea and Gulf of America via the North Equatorial and Caribbean current systems.

Is the amount of Sargassum in the Atlantic/Caribbean increasing?

Since 2011, large accumulations of Sargassum have occurred every year in the Caribbean Sea, Gulf of America, and tropical Atlantic, but the amount can vary from year to year.
The presence of Sargassum occurs over large areas from the tropical Atlantic in the east, to the Gulf of America in the west, approximately 5,000 kilometers from the eastern tropical Atlantic to the west off the Mexican coast in the Caribbean Sea. Sargassum does not extend as a blanket (or blob) covering the full surface of the ocean in these regions. Instead, Sargassum floats in patches that range in size from a few centimeters to hundreds of meters. Some of these patches reach the coastal areas, including beaches, ports, and even intake systems for drinking water. The area that these patches cover has been significantly larger in recent years than prior to 2011.

What are the benefits of Sargassum to ocean ecosystems?

Sargassum, in normal amounts, provides habitat, food, protection, and breeding grounds for hundreds of diverse marine species, including commercially important species, such as tuna and swordfish, that feed on the smaller marine life present in Sargassum mats. If Sargassum reaches the coast in small/normal quantities, it may help to avoid beach erosion.

What are some of the drawbacks to having Sargassum wash ashore?

Out at sea, Sargassum is an important habitat for fish, sea turtles, and other marine organisms, but as it accumulates close to the coastlines it can smother valuable corals, seagrass beds, and beaches. As it washes ashore the seaweed begins to decay, attracting flies and other insects. Additionally, during its breakdown, Sargassum produces hydrogen sulfide gas, which smells of rotten eggs, repelling beachgoers and affecting the tourism industry that depends on pristine ocean conditions. Sargassum can also impact navigation, block water intake in desalination plants, and impact benthic ecosystems after/if they sink to the bottom of the ocean.

What threats, if any, does Sargassum present to human health?

Studies of the impact of Sargassum on human health started very recently and this is a topic that needs more time to be fully understood. However, when decomposed, Sargassum releases hydrogen sulfide (a gas) that may cause respiratory health problems. Sargassum is also known to often contain heavy metals that can be toxic to humans and animals.

NOAA Efforts

What research does NOAA CoastWatch or other parts of NOAA currently conduct on Sargassum?

Researchers at NOAA CoastWatch and AOML alongside the University of South Florida developed the experimental Sargassum Inundation Report (SIR) to provide an overview of the extent of Sargassum in the ocean and the risk of Sargassum washing into coastal waters, beaches, and shorelines in the Caribbean, Gulf of America, and southeast Florida regions.
Research conducted at NOAA in partnership with the University of Miami, the University of South Florida, and LGL Ecological Research (TX) is also aiding to identify how Sargassum extends across the Caribbean, Gulf of America, and tropical Atlantic, by assessing the role of ocean currents, winds, and waves in their motion. This work includes field experiments conducted to monitor the actual path of Sargassum using satellite tracking devices and surface drifters and satellite imagery, and physical representation of Sargassum in theoretical and numerical simulations. Please refer to the end of this document for a list of scientific manuscripts derived from this research.
Additionally, a collaboration between NOAA researchers and the Fearless Fund studies how seaweed, including Sargassum, naturally removes carbon dioxide from ocean waters and sequesters it in the seaweed. This project seeks to provide a management solution to wide-scale inundation of beaches, while also repurposing the Sargassum.

What is the experimental Sargassum Inundation Report?

The experimental Sargassum Inundation Report (SIR) provides an overview of the area of current Sargassum patches and the risk of Sargassum inundation in coastal regions of the Caribbean, tropical Atlantic, and Gulf of America. SIR is an experimental product that updates on a weekly basis and uses satellite-based data to estimate the potential for Sargassum to wash ashore. It is not a forecast.
SIR shows the current conditions of Sargassum density and identifies coastal areas where Sargassum is within 50 km (30 miles) and, therefore, may potentially be impacted by Sargassum in the following days/weeks. The actual occurrence of coastal inundation will largely depend on local current, tide, wind, and wave conditions. The inundation potential is then categorized into three levels: low, medium, and high, which are largely based on the distance between patches of Sargassum to the coast, and the density and extent of these patches. Coastlines are color coded according to these three levels.
SIR serves as a source of information about the present distribution of Sargassum in different areas, potential to reach the coast, and can be used to monitor past movements of Sargassum in the region, which may allow researchers to hypothesize the evolution of the risk in time.

Can you predict where Sargassum is going and when it will arrive?

Researchers are using satellite images to identify areas in the open ocean where Sargassum density is large and estimate where beaching events may occur based on the density and proximity of Sargassum patches from the coast. While this is not a forecast, it does help communities prepare for possible inundation events. Researchers are using their knowledge of ocean currents, winds, and wave conditions to improve these estimates.
Identifying Sargassum from space is complex. Sargassum can be indirectly observed by satellite from space by measuring how light reflects from the ocean surface. NOAA CoastWatch and AOML are conducting research to assess the impact of ocean currents, winds, and waves on the distribution and path of Sargassum, to increase the accuracy of Sargassum pathway models. The Atlantic OceanWatch/Caribbean/Gulf of America Node of CoastWatch (hosted at AOML) produces a monitor with the OceanViewer tool.

What are the satellites that are used to create the Sargassum Inundation Report?

Currently SIRs are created from a satellite-derived quantity (density of Sargassum), which is estimated by the University of South Florida using the NASA MODIS (Moderate Resolution Imaging Spectroradiometer) sensor onboard the NASA Aqua and Terra satellites.
Because MODIS is nearing the end of its mission, NOAA CoastWatch and AOML are working towards the upgrade of this product to integrate data from additional sensors to provide better coverage, especially in coastal areas, such as VIIRS on board SNPP, NOAA-20 and NOAA-21 polar orbiting satellite missions, OLCI (Ocean and Land Colour Instrument ) onboard Sentinel-3A and Sentinel-3B satellites, and MSI (Multispectral Instrument) onboard the ESA (European Space Agency) Sentinel-2A and Sentinel-2B optical satellites.

Have these satellite estimates of Sargassum and coastal inundation been validated with actual observations?

The estimates provided by the SIR have been validated in different areas of the Caribbean Sea and tropical Atlantic Ocean and a publication of this work has been submitted to Elsevier’s Aquatic Botany Journal.

Is there a citizen science effort to monitor Sargassum?

An international citizen science effort to collect mostly coastal observations of Sargassum is led by Florida International University, through the Epicollect Sargassum Watch web pages. Epicollect is a mobile and web application to collect science data. CoastWatch and AOML contribute to this effort through its Sargassum citizen science web page located here.

When might we see significant Sargassum inundation in Florida from the Great Atlantic Sargassum Belt? (Spring 2023)

The motion, extent, and density of Sargassum is very complex - it grows, sinks, and moves according to ocean currents, winds, and waves. Therefore, sometimes it may not be possible to describe trajectories in advance, but rather a general description of how the average extension and density have changed. Projecting an accurate path of Sargassum is challenging and a current area of intense research. At this moment, the timing of Sargassum beaching cannot be predicted.
There are two main sources of Sargassum reaching the Gulf of America , one is local and peaks in April-May, and the second one is the Caribbean Sea which peaks during the summer months.
Large amounts of Sargassum are currently located in the Caribbean Sea, moving towards the Yucatan Peninsula, and spreading through the Gulf of America by the Loop Current. There are two main sources of Sargassum located in the Gulf of America, one is local and peaks in April-May, and the second one is the Caribbean Sea which peaks during the summer months.
The Loop Current flows through the Florida Straits and off the east Florida coast, where it is known as the Florida Current, and into the Gulf Stream as it heads north up the eastern coast of the US. The very strong Loop Current is now transporting moderate amounts of Sargassum that were previously located in the Caribbean Sea, with larger amounts potentially on the way. Some of the Sargassum in the Gulf of America also originates locally. Whether the Sargassum will beach on the coast of Florida, including the Florida Keys, will largely depend on the local wind, wave, and tide conditions. Given the complexity of its motion, growth, and decay, it is not possible to forecast the timing of beaching. However, given the size and number of the current Sargassum patches, there is a strong chance that Sargassum carried by the Florida Current may reach the Florida coast despite wind and wave conditions. As of mid March 2023, satellite observations indicate that some of this Sargassum has already reached the northern coast of Cuba.

How does the size of the 2023 bloom compare to others since Sargassum began to be observed in the tropical Atlantic and Caribbean in 2011?

Sargassum outlooks are published once a month by the University of South Florida. These outlooks show maps with the monthly (past month) extensions of Sargassum. The current (February-March, 2023) total extension of Sargassum in the tropics is similar to the largest events that occurred in previous years (especially 2018), with large extensions of Sargassum observed in the Caribbean Sea being observed since February. While this Sargassum remains at the sea surface and moves with help from ocean currents, winds, and waves, it may grow and increase its density, provided that it encounters warm temperatures and plenty of nutrients. If the large amount of Sargassum that is presently in the Caribbean Sea remains at the surface, it has the potential to spread more widely throughout the Gulf of America and then by the Loop Current and Florida Current (the name of the Gulf Stream off Florida) to reach the Florida Keys and the east Florida coast and Bahamas.

C-HARM: Predicting Harmful Algal Blooms with Satellite Data

v.wegman — Thu, 12 Jan 2023 20:41:44 +0000

C-HARM: Predicting Harmful Algal Blooms with Satellite Data v.wegman Thu, 01/12/2023 - 15:41

Date

March 14, 2023

Category

User Story

Data Applications

Ecosystem Monitoring

Fisheries & Aquaculture

Transportation & Safety

Water Quality

The West Coast Node (WCN) of CoastWatch is home to thousands of datasets; from ACSPO SST to Vector Winds, their ERDDAP server stores decades of historic climate data. But one group of products stands out with its impact on the coastal communities of California and Southern Oregon: C-HARM.

What is C-HARM?

The California-Harmful Algae Risk Mapping (C-HARM) Harmful Algal Bloom (HAB) products predict the occurrences of harmful species of Pseudo-nitzschia and the toxin they produce, domoic acid, using sophisticated circulation models, satellite remote-sensing data, and statistical models. More information regarding the methodology can be found in Anderson et al. 2016. Note that the current version of C-HARM, v3, integrates the West Coast Operational Forecast System (WCOFS).

In layman's terms, C-HARM products are forecasts of toxin levels and Pseudo-nitzschia in coastal waters, developed by applying data from ocean physics models and ocean color satellites to algae probability models. The resulting information can be mapped to create images as shown below, which represent the probability of high levels of Pseudo-nitzchia (left) and cellular domoic acid (right) on February 23, 2023, as predicted three days in advance. Products are also available as one- and two-day forecasts, and as a Nowcast.

What are Pseudo-nitzschia and Domoic Acid?

Pseudo-nitzschia is a common genus of microscopic marine algae, or phytoplankton, of which some species produce a neurotoxin, domoic acid. When these phytoplankton “bloom,” or grow to a population of 10,000 cells per liter of seawater, the resident shellfish are likely to consume Pseudo-nitzschia, and with it, domoic acid.

There are two common measurements for domoic acid (DA): particulate DA and cellular DA. Particulate DA models, or Domoic Acid Event Prediction, predict the concentration of DA in the bloom. The bloom is considered a HAB when there are at least 500 nanograms of domoic acid per liter of affected water. Toxicity is still possible at a lower concentration, but this threshold has been established through multiple studies. C-HARM products predict the percent probability of the bloom reaching this threshold. Cellular DA models, or Domoic Acid Toxicity Prediction, are a forecast measurement for the amount of DA per individual cell of Pseudo-nitzschia (a single-cellular algae as shown above). The threshold for a toxic cell is 10 picograms of domoic acid per cell, which has been established through the same research as the particulate DA threshold. C-HARM products predict the percent probability of the Pseudo-nitzschia containing 10 picograms.

Is Domoic Acid bad?

Domoic acid can build up in shellfish that consume Pseudo-nitzschia without visibly harming them. However, people and animals that eat the toxin-containing shellfish can develop serious illnesses resulting from Amnesic Shellfish Poisoning (ASP). Symptoms can appear as early as 15 minutes after eating shellfish, or even 40 hours later. The most common reactions are typical of food poisoning: vomiting, diarrhea, abdominal pain, etc. that can last several days. Severe cases may result in permanent short-term memory loss, hence the term “Amnesic” Shellfish Poisoning. There is no antidote for domoic acid; treatment is largely limited to hydration maintenance and pain management.

How can consumers avoid Amnesic Shellfish Poisoning?

It is impossible to determine whether a specimen is contaminated without laboratory testing, and domoic acid cannot be eliminated once it has been absorbed into tissue. Cooking or freezing shellfish before eating will not prevent toxication. Therefore, for consumers to continue enjoying California’s coastal critters, it is necessary to avoid shellfish that have been exposed to Pseudo-nitzschia.

How does C-HARM help?

Pseudo-nitzschia blooms and the neurotoxin they produce can be accurately predicted days in advance using forecast models paired with satellite data. C-HARM does just that; by avoiding areas deemed unsafe by C-HARM, consumers are far less likely to contract ASP. Note: Even if shellfish are from a low-risk area, the likelihood of poisoning is never zero.

Domoic acid has become the top issue for the U.S. West Coast. One particularly severe event began in mid-August 2022 in Ventura, and spread along the coast of Southern California over a few weeks. Over 400 sea lions and seals were found stranded with apparent poisoning. C-HARM was used daily to track the bloom and alert necessary response teams, such as the West Coast Marine Mammal Stranding Network. While the report has yet to be published, Clarissa Anderson - Director of the Southern California Coastal Ocean Observing System (SCCOOS) and lead developer of C-HARM - says officials studying the impact of this bloom measured the highest ever DA levels in animal tissue.

The frequency of impact events has only grown in the past 25 years. The ability to accurately predict toxic blooms is crucial for local fisheries, aquaculture, and marine mammal rescue groups to mitigate harm and more effectively manage coastal resources. In its first five years of availability, C-HARM has become a daily necessity for several key sectors.

C-HARM products are available through the CoastWatch West Coast Node ERDDAP, found here.

Colors and Confusion: Making Better Color Choices for Data Visualization

jebidiah.jeffery — Tue, 13 Dec 2022 23:39:12 +0000

Colors and Confusion: Making Better Color Choices for Data Visualization jebidiah.jeffery Tue, 12/13/2022 - 18:39

Date

September 23, 2021

Category

User Story

Data Applications

Climate & Weather

Ecosystem Monitoring

Ocean & Coastal Dynamics

Transportation & Safety

Communication of scientific information and data to the public is part of NOAA’s mission, and scientific visualization is often the public’s first encounter with the agency’s data. As such, adopting modern visualization design guidelines is important. Commonly, color choices for satellite data have been based on convention without careful consideration of the best colors for conveying information. This post gives an overview of recent advances and considerations for selecting and improving color selection for remote sensing data. NOAA CoastWatch will be experimenting with different colors for its data presentations.

How to Choose The Right Color Bar

Sequential Color Bar

The colors of the map are vital to the representation of the data and the understanding of the consumer. For certain visual variables, such as color and orientation, color is usually king. It is usually the first thing people notice. They don’t notice other variables right away. For example, if you were to display sea surface salinity (SSS) for a specific period or time, you might choose a rainbow color pattern because it is appealing to the eye, gets the information across, and visualizes drastic changes. Figure 1 demonstrates the typical rainbow coloration used for surface surface salinity.

Figure 1: Global Sea Surface Salinity on 06-14-19. Rainbow coloration. Source: NOAA CoastWatch.

As Figure 1 demonstrates, the rainbow color pattern is mainly used for eye appeal and to display drastic changes. However, this creates an increased rate of error when identifying the highest and lowest data values. To better represent the data, a sequential color bar should be used. A sequential color bar consists of either grayscale or haline maps. These color styles have a greater change in hue. Changes in hue imply more difference than changes in value or intensity. For example, this type of visualization would allow for easier identification of areas that have the highest and lowest surface sea salinity. This color style is represented in Figure 2. See if you can tell the difference!

Figure 2: Global Sea Surface Salinity on 06-14-19. Preferred: Haline coloration. Source: NOAA CoastWatch.

Diverging Color Bar

Diverging color bars are useful for displaying anomalies, such as sea surface temperature (SST) and sea surface height (SSH). SSH anomalies visualizes changes in SSH over a certain period of time (usually a month or year). Anomaly maps visualize small ranges of data making it important to make a color bar to visually distinguish small changes. An example of a diverging color bar is red → blue or blue → red.

Below, Figure 3 demonstrates how not to visualize anomalies. The contrast between the colors are best for gradual changes in hue, however, for this type of data, the changes are so small that they aren’t gradual enough for someone to notice a significant difference.

Meanwhile, Figure 4 demonstrates how to properly visualize anomalies. While most of the picture is blue, the areas with large anomalies are easily identifiable in red.

Figure 4: Global Sea Surface Height Anomaly on 06-23-19. Preferred: Balance coloration. Source: NOAA CoastWatch.

Picking the Right Color Legend

For the public to really understand what they are visualizing, it is best to keep maps and legends simple. As demonstrated above, a continuous data legend should be used if your data is on a constant gradient. Categorical data legends are best used to display different classifications of data (such as no risk, moderate, severe, etc). This type of data is simple to understand and users can quickly grasp the information. This is best used for displaying data such as sea surface temperature (SST) or any of the examples discussed above. Figure 5 demonstrates how NOAA Coral Reef Watch was able to effectively simplify their color bar legend so it is easy to understand.

NOAA Coral Reef Watch Bleaching Heat Stress Alert Area. Date: 06-24-19. Source: NOAA Coral Reef Watch.

References and Related Readings

Gerst, M.D., M.A. Kenney, A.E. Baer, A. Speciale, J.F. Wolfinger, J. Gottschalck, S. Handel, M. Rosencrans, and D. Dewitt. Using visualization science to improve expert and public understanding of probabilistic temperature and precipitation outlooks. Submitted to Weather Climate and Society.
Thyng, K., Greene, C., Hetland, R., Zimmerle, H., & Dimarco, S. (2016). True Colors of Oceanography: Guidelines for Effective and Accurate Colormap Selection. Oceanography,29(3), 9-13.