Skip to main content

Foundational Data Product Modernized

Updated International Comprehensive Ocean-Atmosphere Data Set

Drifting buoy being cast into ocean
Courtesy of NOAA

As any sailor will tell you, weather and ocean conditions are inextricably linked. Both influence the other. The weather affects the ocean in many different ways such as producing winds that drive ocean currents and create waves. But the ocean also affects the weather and climate in the longer term. For example, a tropical storm can gain energy from warm ocean water and turn the energy into hurricane force. And El Niño and La Niña events, the complex weather patterns resulting from variations in ocean temperatures in the tropical Pacific, can affect weather and climate over land as well. Because understanding these interactions is important to human life and society, people have been collecting data about the ocean and the weather while at sea for hundreds of years.

Our most significant collection of ocean and weather data has been upgraded. We have released version 3.0.2 of the International Comprehensive OceanAtmosphere Data Set (ICOADS), the largest collection of surface marine observations spanning from 1662 to the present. The dataset provides an integrated source of environmental observations such as sea surface temperature, air temperature, sea level pressure, and wind speed and direction. These observations are gathered from a variety of observing platforms including ships, moored and drifting buoys, and fixed platforms like oil rigs and coastal offshore structures. The dataset also includes more recent observations collected through remote sensing and autonomous vehicles such as sail drones. ICOADS provides access to a range of observation types, globally, and through the entire marine instrumental record.

New Input Data Format for ICOADS

ICOADS 3.0.2 now includes near-real-time data transmitted in the Binary Universal Form for the Representation of Meteorological Data (BUFR) format, in combination with the Traditional Alphanumeric Codes (TAC) data. Like TAC, BUFR is maintained by the World Meteorological Organization (WMO) and was created so that any kind of data can be represented with higher previsions and flexibility, along with a complete description of what those data are.

Many of the organizations that report observations in near-real time have moved to the BUFR format to align to WMO policy, so this update brings ICOADS into alignment with the collection and archive of these international data distributions. In addition, the new BUFR format allows for more flexibility as more new observing platforms come online, especially those that report in near-real time. However, data in the TAC format, which has been the traditional format for observational data for over 50 years, is still widely used. Some unique observations are still reported in the TAC format from platforms that are transitioning to BUFR.

By including the BUFR reports, the total number of reports in the new version of ICOADS increased by as much as 30% in recent years as compared to the TAC-based version (R3.0.1), and the spatial ocean coverage for essential climate variables (ECVs) increased by about 20% based on monthly 2°×2° grids. In addition, a new variable for salinity has been included in the new version.

Support from Interconnected Community

While NCEI has the responsibility for the operation and maintenance of ICOADS, the “I” stands for international. ICOADS is informed by the international marine community and long-standing partnerships, such as the U.S. National Center for Atmospheric Research, Florida State University, National Oceanography Centre in the United Kingdom, the German Meteorological Service Deutscher Wetterdienst, and recently, the Fisheries and Oceans Canada. NCEI collects requirements from users at workshops and international conferences such as the International Workshop on Advances in the Use of Historical Marine Climate Data (MARCDAT), the JCOMM Workshop on Advances in Marine Climatology (CLIMAR), and OceanObs’19.

In addition to the international community of scientists, other primary user groups for ICOADS include dataset developers, reanalysis centers, and the satellite community, as well as legal service community. The new release will improve downstream products significantly, such as the Optimum Interpolation Sea Surface Temperature (OISST) v2.1.