National Geographic looks at the rivalry between two early cartographers of Mars who based their maps on observations made during Mars’s “Great Opposition” in 1877: Nathaniel Green, whose Mars “was a delicately shaded world with landforms that gradually rose from vast plains and features that blended into one another” (pictured here) and Giovanni Schiaparelli, whose Mars had more detail—including those famous canals—but was less accurate.
A new study maps the possible locations of subsurface water-ice reservoirs, vital for any crewed missions. [Sky & Telescope]
NASA Earth Observatory: “The map above shows air temperatures across the United States on September 6, 2020, when much of the Southwest roasted in a dramatic heatwave. The map was derived from the Goddard Earth Observing System (GEOS) model and represents temperatures at 2 meters (about 6.5 feet) above the ground. The darkest red areas are where the model shows temperatures surpassing 113°F (45°C).” Heat waves in southern California have become “more frequent, intense, and longer-lasting,” the article goes on to say.
NASA Earth Observatory has had several stories on the western U.S. wildfires, gathered here. This story summarizes the situation; satellite images of the smoke generated by the fires can be seen here, here and here.
One-third of the United States is currently affected by at least moderate levels of drought, NASA Earth Observatory reports.
The map above shows conditions in the continental U.S. as of August 11, 2020, as reported by the U.S. Drought Monitor program, a partnership of the U.S. Department of Agriculture, the National Oceanic and Atmospheric Administration, and the University of Nebraska—Lincoln. The map depicts drought intensity in progressive shades of orange to red and is based on measurements of climate, soil, and water conditions from more than 350 federal, state, and local observers around the country. NASA provides experimental measurements and models to this drought monitoring effort.
According to the Drought Monitor, more than 93 percent of the land area in Utah, Colorado, Nevada, and New Mexico is in some level of drought; 69 percent of Utah is in severe drought, as is 61 percent of Colorado. More than three-fourths of Oregon, Arizona, and Wyoming are also in drought. The effects of “severe” drought include stunted and browning crops, limited pasture yields, dust storms, reduced well water levels, and an increase in the number and severity of wildfires. Most of those areas had no sign of drought in the mid-summer of 2019.
Other raw data sources include the Copernicus Atmosphere Monitoring Service (CAMS), fire activity data from which can be viewed here; and MODIS data from NASA’s Terra and Aqua satellites. For a live feed of MODIS data on the Amazon fires, see the MODIS Wildfire Dashboard.
NASA
Meanwhile, NASA’s Earth Observatory posted MODIS imagery of several Amazon fires, and had this curious statement that seemed to minimize the scale of the problem: “As of August 16, 2019, an analysis of NASA satellite data indicated that total fire activity across the Amazon basin this year has been close to the average in comparison to the past 15 years. […] Though activity appears to be above average in the states of Amazonas and Rondônia, it has so far appeared below average in Mato Grosso and Pará, according to estimates from the Global Fire Emissions Database, a research project that compiles and analyzes NASA data.”
A subsequent NASA Earth Observatory post seems to contradict the one I mentioned earlier, pointing to “a noticeable increase in large, intense, and persistent fires burning along major roads in the central Brazilian Amazon” which “are more consistent with land clearing than with regional drought” and noted fire detections “higher across the Brazilian Amazon” since 2010.
Contextualizing the amount of fires seems to be a recurring theme in the reporting: the number of fires are up sharply over last year, but close to the average when taking a longer view. It’s helped a lot of bad and insincere actors make it harder to get to the heart of what’s going on over there. They can’t, after all, deny the satellite imagery or the remote sensing: we can see the fires. We can detect the emissions of smoke, carbon dioxide and carbon monoxide (1, 2, 3). We can map them. And those maps can help us understand what’s going on.
On the NGO front, InfoAmazonia has produced the above map comparing fires over the last 24 hours with historical fire data. (They have other maps on this subject as well.)
The NASA Applied Sciences Program has partnered with the Centers for Disease Control and Prevention (CDC) to create the first publicly available map of ultraviolet (UV) radiation for all counties in the contiguous United States. The dataset, which spans 2005-2015, is available on the CDC’s National Environmental Public Health Tracking network, which delivers information and data about health issues related to environmental factors. Public health officials, city planners, or individuals concerned about Sun exposure can learn how much ultraviolet radiation is falling over each county each month, which is an important step in helping reduce skin cancer risks.
The animated map above shows the monthly average UV dose in 2015.
This interferogram shows the ground displacement caused by last week’s earthquakes in southern California. Produced by NASA’s Jet Propulsion Laboratory, it’s based on synthetic aperture radar (SAR) images from JAXA’s ALOS-2 satellite taken both before (16 April 2018) and after (8 July 2019) the earthquakes. Each colour cycle represents 12 centimetres (4.8 inches) of ground displacement.
Writing for Crosscut, Tom Reese memorializes his father, who worked as a cartographer and engineer for NASA’s Aeronautical Chart and Information Center during the Apollo program. Harlan Reese left behind a collection of maps, photos and charts in his garage which, Tom says, still contains “mesmerizing detail and mystery”:
One box has odds and ends of early lunar photography, some of the prints overlain with Dad’s hand-drawn compass points, landing site X’s and handwritten notations. The images were made through large telescopes on Earth, by the Surveyors and Rangers and Lunar Orbiters and early Apollos flying around and over the most promising landing sites. You can also see those smudged fingerprints that likely belong to Dad, mixed with those of many others who used magnifiers and X-Acto knives to carefully slice apart select sections of crater fields. Some small globs of cracked glue remain where they dripped during the process of pasting together the cut pieces to form mosaics of the unexplored landscape.
Some small indentations probably show how the prints were positioned in viewing devices like the extremely precise optical comparator, which helped human eyes interpret the length of shadows inside craters for the first time. These results were coordinated with data about altitude and lunar daylight to provide the most precise terrain measurements possible. Careful airbrushing would smooth over and fill in terra incognita with educated guessing. Finally, this data would be transformed into the precisely printed maps and charts that would help lunar lander pilots to, among other things, second-guess in real time the navigation decisions made by computers of the late 1960s and early 1970s.
NASA Earth Observatory maps the bitterly cold temperatures resulting from cold air pushed southwards by an unstable polar vortex. The maps and animations are by Earth Observatory’s lead cartographer, Joshua Stevens. On Twitter he posted a companion visualization showing what’s happening on the other side of the planet, where a searing heat wave is blistering Australia.
The San Francisco Chronicle’s 2018 California Fire Tracker is an interactive map of ongoing and contained wildfires—notably, at this moment, the Camp and Woolsey fires. It includes fire perimeter and air quality data. (Note: it’s glitchy on desktop Safari.)
Carbon monoxide released into the atmosphere by the California wildfires is drifting across North America in concentrations sufficient to turn up on the Atmospheric Infrared Sounder (AIRS) on NASA’s Aqua satellite. A series of maps showing CO concentrations in the United States between 30 July and 7 August, using AIRS data, have been combined into the animation above.
Landsat observations have charted the erosion of the banks of the ever-changing Padma River, a major distributary of the Ganges in Bangladesh. This is vividly shown in this animation produced by NASA Earth Observatory, which “shows 14 false-color images of the Padma river between 1988 and 2018 taken by the Landsat 5 and 8 satellites. All of the images include a combination of shortwave infrared, near infrared, and visible light to highlight differences between land and water.” More on the erosion of the Padma River here.
NASA Earth Observatory: “The map above depicts changes in water storage on Earth—on the surface, underground, and locked in ice and snow—between 2002 and 2016. Shades of green represent areas where freshwater levels have increased, while browns depict areas where they have been depleted. Data were collected by the GRACE mission, which precisely measured the distance between twin spacecraft as they responded to changes in Earth’s gravity field. In sensing the subtle movements of mass around the planet, the satellites could decipher monthly variations in terrestrial water storage.” The GRACE observations form the basis of a study published this month in Nature on changes in global fresh water availability. More at the JPL’s GRACE-FO project page. [Benjamin Hennig]
National Geographic looks at the rivalry between two early cartographers of Mars who based their maps on observations made during Mars’s “Great Opposition” in 1877: Nathaniel Green, whose Mars “was a delicately shaded world with landforms that gradually rose from vast plains and features that blended into one another” (pictured here) and Giovanni Schiaparelli, whose Mars had more detail—including those famous canals—but was less accurate.
