On the roof of the Exploratorium, attached to a buoy, and anchored underwater, a variety of state-of-the-art sensors are gathering data that helps us understand the changing conditions of the Bay, the atmosphere, and our local environment.
The Exploratorium owns and operates many of the sensors, while others are on loan from NOAA or other science agencies and institutions. Data from the sensors are displayed here and shared with regional and national data networks.
Bay Water Sensors
Bay Water Probe (Bottom)
| Location: | Anchored underwater one meter above the Bay floor, near the northeast corner of Pier 17 (the pier adjacent to the Exploratorium) |
| Measures: | Bay water temperature, salt content (salinity), tidal height, dissolved oxygen, and sediment content (turbidity) |
Salinity and temperature together determine the density of water, which drives ocean circulation—denser water sinks beneath less dense water.
This sensor is provided and maintained by the US Geological Survey.
Water Currents Sensor
| Location: | Northeast corner of the Exploratorium’s roof |
| Measures: | Speed and direction of Bay water surface currents |
This antenna sends out radio waves that bounce off the surface of the water. The antenna compares the wavelengths of the reflected wave and the transmitted wave to figure out how fast the water is moving.
By combining data from many current current antennas around the Bay, the CeNCOOS network creates a live picture of surface currents, which are driven by tides and wind.
Bay Water Probe (Surface)
| Location: | In the water between piers 15 and 17 |
| Measures: | Bay water temperature, salt content (salinity), dissolved oxygen, and sediment content (turbidity) |
Salinity and temperature together determine the density of water, which drives ocean circulation—denser water sinks beneath less dense water.
Carbon Dioxide Buoy
| Location: | Floating between Piers 15 and 17 |
| Measures: | Carbon dioxide (CO2) in the atmosphere and in Bay water. Carbon dioxide is a gas that traps heat in Earth’s atmosphere. |
Our buoy is part of a global network measuring carbon dioxide in the ocean and atmosphere. Researchers are using this data to learn how CO2 moves between the ocean and atmosphere. Rising CO2 levels in the ocean are harming organisms like corals and oysters.
Our buoy is on loan from NOAA's Pacific Marine Environmental Lab.
Air Quality and Atmospheric Sensors
Radiometer
| Location: | On the roof of the Exploratorium’s Fisher Bay Observatory Gallery |
| Measures: | Air temperature, pressure, wind, and humidity at a range of elevations |
A radiometer uses radio waves to profile atmospheric conditions from ground level up to about one kilometer. This layer of the atmosphere that’s closest to Earth’s surface—the boundary layer—gets thicker and thinner as the planet heats and cools every day.
We submit our data to a boundary layer network operated by Earth Networks.
Air Quality Sensors
| Location: | Two sensors: one on the roof of the Exploratorium (near the Bay), and one at the other end of the building (near a busy street—the Embarcadero) |
| Measures: | Carbon dioxide (CO2) in the air, as well as pollutants such as nitrogen dioxide (NO2), carbon monoxide (CO), and ozone (O3) |
A network of these sensors around the Bay Area—called BEACON—creates a map of changing carbon dioxide levels over time.
Carbon dioxide is a gas that prevents heat from escaping Earth’s atmosphere. Excess CO2 from burning fossil fuels is the primary cause of global warming.
Weather Sensors
Weather Station
| Location: | Roof of the Exploratorium’s Fisher Bay Observatory Gallery |
| Measures: | Air temperature, humidity, air (barometric) pressure, wind speed and direction, and rainfall—all fundamental measurements used in weather reporting and forecasting |
Rain Disdrometer
| Location: | Roof of the Exploratorium’s Fisher Bay Observatory Gallery |
| Measures: | Raindrop size and velocity using a scanning laser |
Raindrops come in a wide range of sizes, depending on how much water the clouds contain, and the weather conditions in which the raindrops form and travel. Strong Pacific winter storms, also known as atmospheric rivers, have bigger, faster raindrops than mild rainstorms do.
Visibility Sensor
| Location: | On the northeast corner of Pier 17 (the pier adjacent to the Exploratorium) |
| Measures: | Visibility in nautical miles by sending and receiving infrared light signals |
Fog often limits visibility in the Bay Area, making it hard for ships and aircraft to navigate. Visibility data helps operators know how to proceed safely.
The data is distributed by NOAA’s Weather Observation Network.
Other Sensors
Heat Camera
| Location: | Roof of Exploratorium near the Embarcadero |
| Measures: | Heat (infrared radiation) coming from objects nearby |
This camera captures infrared light—produced by heat radiation. It reveals how different objects, such as trees or buildings, absorb and reflect sunlight differently, making them hotter or colder.
Camera (Visible Light)
| Location: | Roof of the Exploratorium’s Bay Observatory Gallery |
| Measures: | Live images of the view toward the Bay Bridge |
