An official website of the United States government.

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Legacy Publications Explorer

You are here: Publications / Publication Details

Publication Details

Please note this explorer contains 2017 and prior publications and is no longer updated. Visit Data Reports Explorer for the latest NCCOS research data and reports.

Initial skill assessment of the California Harmful Algae Risk Mapping (C-HARM) system

Author(s): Anderson, Clarissa R.; Raphael M. Kudela; Mati Kahru; Yi Chao; Leslie K. Rosenfeld; Frederick L. Bahr; David M. Anderson; Tenaya A. Norris


Name of Publisher: Elsevier

Publication Type: Journal Article

Journal Title: Harmful Algae

Date of Publication: 2016

Reference Information: 59: 1-18.

Keywords: Domoic acid; DINEOF; Ocean color; ROMS; Ecological forecasting; Ocean observing; C-HARM; ECOHAB

Abstract: Toxic algal events are an annual burden on aquaculture and coastal ecosystems of California. The threat of domoic acid (DA) toxicity to human and wildlife health is the dominant harmful algal bloom (HAB) concern for the region, leading to a strong focus on prediction and mitigation of these blooms and their toxic effects. This paper describes the initial development of the California Harmful Algae Risk Mapping (C-HARM) system that predicts the spatial likelihood of blooms and dangerous levels of DA using a unique blend of numerical models, ecological forecast models of the target group, Pseudo-nitzschia, and satellite ocean color imagery. Data interpolating empirical orthogonal functions (DINEOF) are applied to ocean color imagery to fill in missing data and then used in a multivariate mode with other modeled variables to forecast biogeochemical parameters. Daily predictions (nowcast and forecast maps) are run routinely at the Central and Northern California Ocean Observing System (CeNCOOS) and posted on its public website. Skill assessment of model output for the nowcast data is restricted to nearshore pixels that overlap with routine pier monitoring of HABs in California from 2014 to 2015. Model lead times are best correlated with DA measured with solid phase adsorption toxin tracking (SPATT) and marine mammal strandings from DA toxicosis, suggesting long-term benefits of the HAB predictions to decision-making. Over the next three years, the C-HARM application system will be incorporated into the NOAA operational HAB forecasting system and HAB Bulletin.

Availability: Available form NCCOS Publications Explorer and from the publisher.

Location URL:

Note to readers with disabilities: Some scientific publications linked from this website may not conform to Section 508 accessibility standards due to the complexity of the information being presented. If you need assistance accessing this electronic content, please contact the lead/corresponding author, Primary Contact, or