Sargassum events remain a significant problem for coastal communities in the Latin American, Caribbean and African regions. The scale and complexity of coastlines in these regions, combined with the nature of the Sargassum inundations have made it especially difficult for coastal managers to effectively monitor Sargassum beaching events.

To assist with this problem, this working paper applies a rapid monitoring approach developed within the SARTRAC project to assess sargassum events. The approach described in section 2, combines field, anecdotal and technological measures. Together, these measures can support standardised Sargassum monitoring procedures. This working paper applies the Sargassum Data collection form (Anderson, 2021) that can be found in SARTRAC working paper 3.

A universal Sargassum data collection form can provide coastal managers with information on the size and nature of a sargassum event. Following Fidai et al (2020:9), within the SARTRAC project, a sargassum event is defined as “a continuous bloom of any Sargassum in open oceans, or, an aggregation of landed sargassum, with the potential to disrupt social, economic or ecosystem functioning, or to impact human health.” Having standard parameters measured across affected areas can improve comparison between events over time, and between sites. It can also assist in the identification of where sargassum events are repeatedly occurring, and the severity of impacts.

Since 2011, nations in the Caribbean and west Africa have experienced large influxes of the seaweed Sargassum arriving on the nearshore and coasts. These influx events often coincide with summer months, and affect fisheries, turtle nesting and beach activities including tourism. While Sargassum has been prevalent in these regions prior to 2011, as a response to the sudden and large increase in quantities experienced there has been a plethora of management approaches, conducted privately and by government bodies, and of regional conferences to address the “urgent threat” (‘Regional Agreement on Sargassum 2019’ 2019). Climate change is creating environmental phenomena that are not recognisable in the context of the past, of which Sargassum is one possible case (Wang et al. 2019; Johns et al. 2020). This article explores the response to Sargassum since 2011 as a case study of how states and regional institutions may need to develop dynamic interpretations of policy problems as to effectively adapt to a rapidly changing environment.

The aim of this working paper is to provide guidance to new remote sensing researchers who are investigating Sargassum by offering a comparison of two commonly used programming languages for interpreting satellite imagery – Interactive Data Language (IDL) and Python.

IDL is a programming language which is popular in image processing and in space science. ENVI image processing package is written in IDL which allows the user to exploit libraries associated with ENVI. However, it is not freely available. Python is a popular general-purpose programming language with a wide range of applications and is open source. Both are suitable options for detecting ocean surface Sargassum blooms in satellite imagery. This paper provides a comparative overview of the pros and cons of using each of these languages.