instruments

Tracking emissions by satellite

June 20, 2025 By EarthWise Leave a Comment

Carbon dioxide and nitrogen oxides are two of the most problematic human-generated air pollutants that negatively impact air quality, the climate, and human health. Satellites are an important tool for monitoring emissions of these pollutants, but they have limitations. For the most part, satellites have limited spatial resolution, meaning that they can’t reliably narrow down the source of emissions sufficiently to pin down a specific location such as a power plant.

Until now, there have been no instruments that can detect both carbon dioxide and nitrogen oxide simultaneously with high spatial resolution. Often just nitrogen oxide measurements are made, and carbon dioxide levels estimated based on the fact that both are emitted together with typical ratios.

A German research team from the Max Planck Institute and the Heidelberg Institute have developed a technology for the EnMAP environmental satellite to detect both gases with an unprecedented spatial resolution of 30 meters. Data from the satellite makes it possible to track multiple sources of emission plumes over several tens of kilometers.

The EnMAP system was originally designed for remote sensing of land surfaces. The new research demonstrates that reliable measurements of trace gases are possible even with an instrument not specifically designed for atmospheric observations. When using it, it’s possible to determine the distribution of carbon dioxide and nitrogen oxide in emission plumes from individual power plants. The ability to measure both gases individually means that conclusions can be drawn about the technology, efficiency, and operating mode of the systems being measured.

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German satellite measures CO2 and NO2simultaneously from power plant emissions for the first time

Photo, posted September 19, 2020, courtesy of Sandor Somkuti via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The World’s Hottest Day | Earth Wise

July 27, 2023 By EarthWise Leave a Comment

Early in July – for four days in a row – the average global temperature was the highest ever recorded. As many places around the world endured dangerous heatwaves, the average global temperature on the fourth of July reached 62.92 degrees Fahrenheit, the highest ever recorded by human-made instruments. On July 6th, the global temperature climbed even further to 63.01 degrees.

The average global temperature on an annual basis was about 56.7 degrees from the 1880s through the 1910s. Temperatures rose a bit after that but ended up about 57.2 degrees until the 1980s. After that, temperatures have risen fairly steadily as heat-trapping gases have accumulated in the atmosphere driving the current average above 58 degrees.

Global temperatures have only been directly measured since the mid-20th century. There are proxy measurements from sources like tree rings, ice core samples, glacier measurements, and more that indicate that the recent readings may be the warmest days the earth has seen in millennia.

Average global temperature is determined using temperature readings at thousands of locations on both land and sea across the entire planet. Those readings are compared with average temperatures at those locations for the date and the difference (known as the temperature anomaly) used to calculate a global average.

With the recent arrival of the El Niño in the Pacific Ocean, it is likely that the warming already being driven by greenhouse gas accumulation will intensify further.

In a summer already marked by extreme heatwaves in many locations, having the entire planet 4 or 5 degrees hotter than normal is a very big deal and most certainly not a record to celebrate.

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Earth reaches hottest day ever recorded 4 days in a row

Photo, posted October 29, 2008, courtesy of Darek via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Keeping The Keeling Curve Going | Earth Wise

March 21, 2023 By EarthWise Leave a Comment

The world’s longest-running record of direct readings of carbon dioxide levels in the atmosphere is the Keeling Curve, measurements taken at the summit of Mauna Loa in Hawaii. The readings have been going on with almost no interruption since Charles Keeling began taking them in the 1950s. But the eruption of Mauna Loa last November toppled power lines at the mountaintop observatory and buried a mile of the main road up the mountain in lava.

Scientists have been scrambling to resume measurements and the near-term solution has been to take them, for the first time, on Mauna Kea, the neighboring large volcano about 25 miles away. The National Oceanic and Atmospheric Administration flew in and installed instruments at the Mauna Kea observatory so that only about a week went by without measurements. It happened so quickly because months earlier, NOAA had already started looking into installing a backup site on Mauna Kea where there is an observatory run by the University of Hawaii.

NOAA used helicopters to install solar panels and batteries on Mauna Loa to restore power in the short term since it will be months before a new road can be built on the still-cooling lava. The plan is to collect parallel measurements for a year to see if Mauna Kea, which hasn’t erupted for thousands of years, might become a long-term backup for Mauna Loa.

The Hawaiian volcanoes are uniquely suited for the measurements because they are surrounded by thousands of miles of empty ocean and are very high up, away from towns, cars, and forests. Scientists are now monitoring measurements from the two sites to see how they compare.

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Battling Lava and Snowstorms, 2.5 Miles Above the Pacific

Photo, posted November 2, 2015, courtesy of Neal Simpson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Reduced Air Travel And Weather Forecasts | Earth Wise

December 16, 2020 By EarthWise Leave a Comment

There have been countless stories about the major and minor changes in the world caused by the Covid-19 pandemic. A few of those changes, such as reductions in pollution and traffic, have been positive. Most have been decidedly negative.

One of the stranger things that has happened is that the pandemic has affected the quality of weather forecasting by sharply reducing the amount of atmospheric data routinely collected by commercial airliners.

It turns out that atmospheric observations from passenger and cargo flights are among the most important data used in weather forecasting models. These observations are made by instruments aboard thousands of airliners, mostly based in North America and Europe. The observation program has been in place for decades. The data is transmitted in real time to forecasting organizations around the world, including the National Weather Service. About 40 airlines participate in the program, which has equipment aboard about 3,500 aircraft. Here in the US, Delta, United, American, and Southwest Airlines participate, as do UPS and FedEx.

During the first few months of the pandemic, air traffic declined by 75% or more worldwide. As a result, atmospheric observations dropped by the same percentage. A government research study showed that when weather forecasting models receive less data on temperature, wind, and humidity from aircraft, the accuracy of forecasts was reduced.

The amount of data from aircraft has increased in recent months as air travel has picked up to roughly 50% of pre-pandemic levels. So, the observation program is on the mend. Nonetheless, impaired weather forecasting is just another unexpected result of the global pandemic.

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Slump in Air Travel Hindered Weather Forecasting, Study Shows

Photo, posted July 15, 2017, courtesy of Daria Nepriakhina via Flickr. Photo by Photo by Daria / epicantus.

Earth Wise is a production of WAMC Northeast Public Radio.

Saildrones For Science

July 11, 2018 By EarthWise Leave a Comment

Nine years ago, engineer Richard Jenkins broke the world land speed record for a wind-powered vehicle with a sailboat on wheels driving across a dry lakebed at 126 miles per hour. After years of engineering development, his technology has now taken on the form of a saildrone that can autonomously sail the sea gathering ecologic, oceanic and atmospheric data.