Evaluating SST Retrieval Masking Under Volcanic Ash Conditions
Abstract
This report examines the capability of the Naval Research Laboratory (NRL) Sea Surface Temperature (SST) software suite to provide valid SST retrievals under conditions where recent volcanic activity introduces plumes of sulfur dioxide (SO) and other contaminants into the atmosphere. We evaluate SST retrievals under conditions of expected volcanic contamination and compare their characteristics relative to retrievals produced during periods of low volcanic influence, verifying that retrievals significantly affected by volcanic contamination are appropriately flagged while unaffected retrievals in clear or low contamination areas are retained. In particular, we examine conditions in a wide area, from 120E to 0E and between 30N and 65N, comparing retrievals in the month after the Raikoke volcano eruption on 22 June 2019 with retrievals from the same time period in 2014, when little volcanic activity extending into the stratosphere was observed. Reliability of the SST retrievals is evaluated with a previously developed method based on the orbital overlap that occurs with recent sun synchronous satellites. The standard deviations of the NRL SST as determined by the orbital overlap method show a value of 0.52K in 2014 without measurable volcanic activity in the area. This value only increases to 0.64K for the same region a month after the Raikoke eruption when a significant concentration of SO is present in the stratosphere. In the vicinity of the volcano, stronger contamination is readily detected and few SST retrievals are produced. We find that the present NRL SST software successfully excludes retrievals strongly affected volcanic plumes while allowing retrievals where he effects are found to be minor.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 25, 2021
- Accession Number
- AD1155870
Entities
People
- Charlie N. Barron
- Jackie C. May
- Jean-francois Cayula
Organizations
- United States Naval Research Laboratory