# Product Tutorial on Sea Surface Temperature (SST)

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## Chapter I: Why is Sea Surface Temperature an important parameter?

### Table of Contents

- Why is Sea Surface Temperature an important parameter?

### Why is Sea Surface Temperature an important parameter?

#### Sea Surface Temperature is an Essential Climate Variable (ECV)

An Essential Climate Variable (ECV) is a physical, chemical or biological variable or a group of linked variables that critically contribute to the characterization of Earth's climate (source: gcos.wmo.int). Sea Surface Temperature (SST) is an ECV.

#### Climate change assessment

The surplus of energy absorbed by the climate system is retained by the ocean due to its large mass and heat capacity. Since this energy is used to warm up the ocean, measuring SST allows us to determine if changes in the surplus of energy have occurred. SST can thus be used to estimate climate change on a global scale.

#### Fisheries management

Thermal fronts and upwelling regions can be identified in SST maps, usually indicating zones that would be prosperous for fishing.

#### Marine ecosystems monitoring

The development of different ocean-based biological organisms depends on the local temperature: ocean temperature variations can affect the species of plants, animals, and microbes that may be found in a certain region. SST changes can cause changes to the migration of species and impact their breeding patterns (source: www.epa.gov/climate-indicators/climate-change).

#### Red tides monitoring

It has been suggested that SST variation contributes, among other factors, to the frequency and intensity of harmful algae blooms, known as red tides. The increase of SST first causes coral bleaching and can eventually lead to coral death, drastically reducing ocean biodiversity since coral is a habitat for many unique species. SST anomaly maps are currently being used as a tool to monitor the state of coral reefs. NOAA is operationally producing maps of bleaching alert areas.

(source: https://www.ospo.noaa.gov/Products/ocean/cb/baa/index.html)

#### Weather conditions monitoring/forecasting

Weather systems are very responsive to changes in surface temperature distribution. As SST is the boundary condition to the atmosphere, it is essential information for atmospheric modeling and weather forecasting. Many studies suggest the relation between SST increase and the frequency and intensity of hurricanes. Changes in the distribution of the SST can also change storm tracks, and therefore can potentially contribute to droughts in some regions.

Ocean currents and eddies can easily be distinguished in SST maps and the position of these systems is of great importance as they impact local weather conditions. For instance, the Gulf Stream keeps sea surface temperatures warm, causing the areas around it to be warm and more hospitable to aquatic life.

SST maps can be used to identify low level coastal jets, since this phenomenon coexists with coastal upwelling, which causes the rising of deeper and cooler water to the surface, easily detected in SST maps.

Other weather phenomenas are highly correlated with SST, such as the Mediterranean intense rain events, a periodic process that takes place in the autumn, affecting areas such as Southern France and Eastern Spain, causing flash flooding over land.

El Niño and La Niña SST phenomena can be monitored with SST maps.