For the 2017 solar eclipse, NASA published eclipse maps that took the irregular umbral shadow of the moon into account: the umbra is neither circular nor oval but irregular—more polygonal—thanks to the uneven topography and elevation of both the moon and the earth. Not accounting for that introduces errors into the map that could make the difference between observing a partial rather than a total eclipse. The process behind those more accurate eclipse maps, which involves computer processing of both lunar and terrestrial elevation models, has now been published in The Astrophysical Journal. [Bad Astronomy]

Launched in December 2022, the Surface Water and Ocean Topography (SWOT) satellite measures ocean surface topography—i.e., sea surface height. It recently completed its first full 21-day science orbit, which is represented in the above animated globe.

The animation shows sea surface height anomalies around the world: Red and orange indicate ocean heights that were higher than the global mean sea surface height, while blue represents heights lower than the mean. Sea level differences can highlight ocean currents, like the Gulf Stream coming off the U.S. East Coast or the Kuroshio current off the east coast of Japan. Sea surface height can also indicate regions of relatively warmer water—like the eastern part of the equatorial Pacific Ocean during an El Niño—because water expands as it warms.

Sea surface height has been measured by earlier satellites (previously); SWOT does so at a much greater level of detail.

Satellite observations have made it possible to evaluate the success of Ukraine’s wheat and barley harvest, even in active war zones or occupied territories. NASA Earth Observatory reports that the harvest was, in the end, larger than expected: “At the outset of Russia’s full-scale invasion in February, some analysts cautioned that 20 to 30 percent of Ukraine’s winter crops might not be harvested at the end of the summer. However, NASA Harvest’s analysis indicates that 94 percent of the winter crop was harvested, including 88 percent of winter crops in areas not controlled by Ukraine.”

A dust plume from the Sahara, driven by an atmospheric river, blew across western Europe this week, and friends from Spain to Germany experienced it. NASA Earth Observatory has satellite imagery of the plume, plus maps (above) showing “a model of the dust plumes blowing across North Africa and into Europe on March 14 and 15. The model was generated by the Goddard Earth Observing System Model, Version 5 (GEOS-5), a global atmospheric model that uses mathematical equations to represent physical processes. Measurements of physical properties like temperature, moisture, and wind speeds and directions are routinely folded into the model to keep the simulation as close to observed reality as possible.”

It turns out that the Geostationary Lightning Mapper (GLM) aboard the GOES-16 and GOES-17 earth observing satellites can do more than just detect lightning—it can also detect bolides, or very bright meteors, thanks to a new automatic detection algorithm. NASA Earth Observatory: “The map above shows the distribution of more than 3,000 bolides detected by the GLMs aboard GOES-16 and GOES-17 between July 2017 and January 2022. Blue points are bolides detected by GOES-16; pink points were detected by GOES-17. The lone pink point over the Atlantic Ocean was detected by GOES-17 during its commissioning phase before it was moved into its operational orbit over the West Coast.” (Bolides in the middle of the map are detected by both, and as you can see there’s a bit of parallax.)

NASA Earth Observatory:

Funded by NASA’s Carbon Monitoring System, scientists recently built a new series of maps detailing the geography of methane emissions from fossil fuel production. Using publicly available data reported in 2016, the research team plotted fuel exploitation emissions—or “fugitive emissions” as the UNFCCC calls them—that arise before the fuels are ever consumed. The maps delineate where these emissions occur based on the locations of coal mines, oil and gas wells, pipelines, refineries, and fuel storage and transportation infrastructure. The maps were recently published at NASA’s Goddard Earth Sciences Data and Information Services Center (GES DISC). (Note that 2016 was the most recent year with complete UN emissions data available at the time of this study.)

The latest of the Landsat satellites, Landsat 9, launched on September 27. Similar to Landsat 8 with slight equipment upgrades, it will replace Landsat 7 when it is fully operational next year. Right now it’s going through its 100-day check-out, after which NASA will hand it over to the USGS. As part of that check-out, its first images were recently released. [NASA Earth Observatory]

VERITAS is one of two missions to Venus announced by NASA last week. Expected to launch between 2028 and 2030, VERITAS will produce an improved map of the Venusian surface with its two instruments: synthetic aperture radar to generate a high-resolution 3D topographic map, and a spectral emissions mapper to map rock types. News coverage: CNN, Global News, Slate, The Verge. Background from NASA; analysis from the Planetary Society.

A new study maps the possible locations of subsurface water-ice reservoirs, vital for any crewed missions. [Sky & Telescope]

Kenneth Field’s virtual globe of Mars follows in the footsteps of his 2016 map.

Interactive maps showing the locations and paths of the Curiosity and Perseverance rovers. [Maps Mania]

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.

In today's Sunday edition of @washingtonpost pic.twitter.com/qHosujRKrG

— Lauren Tierney (@tierneyl) September 13, 2020

Marena Brinkhurst of Mapbox has a comprehensive list of open data sources relating to the wildfires, smoke, and air quality.

Mark Altaweel at GIS Lounge looks at how GIS is being used to map wildfires, smoke and air pollution.

Previously: California Wildfires, 2020 Edition.

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.

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.)

Note, too, the reference above to burning along major roads. Tim Wallace crunches MODIS date from 2012 onward and teases out some patterns in the fires.

And the New York Times, where Tim used to work, has a map correlating the position of the current Amazon fires along the edges of past deforestation. The Times also has maps showing maps on a month-by-month basis and comparing August 2019 with the August average over the past decade.

[CityLab, Maps Mania]

NASA Earth Observatory:

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.

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.

Below, a Target of Opprtunity Flight Chart for the Apollo 11 mission:

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.

Meanwhile on the other side of the planet ?, @NASA ?️ data shows #Australia's daytime temperatures are soaring (≥40 °C) pic.twitter.com/hvBuEez4G6

— Joshua Stevens (@jscarto) January 31, 2019

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.)

Two Esri maps: a general wildfire map and a map of smoke from wildfires [Maps Mania]. Add to that a map of field damage reports in the area hit by the Camp Fire [Maps Mania].

The Jet Propulsion Laboratory has produced a map of the damage from the Camp Fire based on satellite radar images. NASA Earth Observatory has maps and animations showing the impact of the Camp Fire on air quality and satellite images of the Woolsey Fire burn scar.

The New York Times has a map tracking air quality in California. Smoke from the fires has reached the east coast: an outcome predicted by atmospheric models (see above map).

This interactive map from NBC News that superimposes the Camp Fire on any location to help people outside California get a sense of how big these fires are. [Maps Mania]

Last week a magnitude-7.5 earthquake struck the Indonesian island of Sulawesi, triggering a tsunami that struck the city of Palu with far more force than expected. The New York Times has multiple maps and aerial images of the damaged areas; NASA Earth Observatory has before-and-after Landsat imagery.

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.

Previously: Mapping the Northern California Wildfires.

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.

The Washington Post maps the largest of the wildfires burning in northern California: the Carr Fire threatening the city of Redding and surrounding communities. The Redding Record Searchlight has drone footage of the destruction wreaked by the Carr Fire in Shasta County. NASA has natural and false-colour imagery (Earth Observatory, Visible Earth) of the Carr Fire, as well as the Ranch and River Fires to the south, the so-called Mendocino Complex. See the Mercury News’s fire map of the Mendocino Complex, whose two fires’ combined acreage is now larger than the Carr Fire. Meanwhile, German astronaut Alexander Gerst observed the California wildfires from the International Space Station. [San Francisco Chronicle]

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]

NASA Earth Observatory:

Global sea level rise has been accelerating in recent decades, according to a new study based on 25 years of NASA and European satellite data. This acceleration has been driven mainly by increased ice melting in Greenland and Antarctica, and it has the potential to double the total sea level rise projected by 2100[. …]

The rate of sea level rise has risen from about 2.5 millimeters (0.1 inch) per year in the 1990s to about 3.4 millimeters (0.13 inches) per year today. These increases have been measured by satellite altimeters since 1992, including the TOPEX/Poseidon, Jason-1, Jason-2, and Jason-3 missions, which have been jointly managed by NASA, France’s Centre national d’etudes spatiales (CNES), the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT), and the U.S. National Oceanic and Atmospheric Administration (NOAA). The maps on this page depict the changes in sea level observed by those satellites between 1992 and 2014.

NASA’s Socioeconomic Data and Applications Center (SEDAC) has produced a population estimation service “for estimating population totals and related statistics within a user-defined region.” Basically, it provides a population estimate for an area drawn on a map. Available as data via map and GIS clients, it’s also accessible via a web app. I’ve noodled about with it; its population estimates are generally not insane. [Kottke]

Cape Town is running out of drinking water, a crisis dramatically depicted by NASA Earth Observatory maps that show the depletion of the city’s reservoirs. The animated gif above, for example, “shows how dramatically Theewaterskloof [Cape Town’s largest reservoir] has been depleted between January 2014 and January 2018. The extent of the reservoir is shown with blue; non-water areas have been masked with gray in order to make it easier to distinguish how the reservoir has changed. Theewaterskloof was near full capacity in 2014. During the preceding year, the weather station at Cape Town airport tallied 682 millimeters (27 inches) of rain (515 mm is normal), making it one of the wettest years in decades. However, rains faltered in 2015, with just 325 mm falling. The next year, with 221 mm, was even worse. In 2017, the station recorded just 157 mm of rain.”

The deep freeze is unevenly distributed. NASA Earth Observatory published this temperature anomaly map based on data from the MODIS instrument on NASA’s Terra satellite. A temperature anomaly map shows how much warmer or colder temperatures are versus the average—in this case, land surface temperatures from 26 December 2017 to 2 January 2018 are compared to the 2001-2010 average for the same period. While it’s awfully cold in Canada, and the central and eastern United States, it’s warmer than normal in the southwest. And if you look beyond the North American continent (which is something people should do more often), it’s generally warmer worldwide, particularly in Europe and Asia:

NASA’s Goddard Space Flight Center produced this visualization, based on computer modelling and data from Earth observing satellites, tracking how hurricanes transport sea salt, dust, and smoke across the globe.

During the 2017 hurricane season, the storms are visible because of the sea salt that is captured by the storms. Strong winds at the surface lift the sea salt into the atmosphere and the particles are incorporated into the storm. Hurricane Irma is the first big storm that spawns off the coast of Africa. As the storm spins up, the Saharan dust is absorbed in cloud droplets and washed out of the storm as rain. This process happens with most of the storms, except for Hurricane Ophelia. Forming more northward than most storms, Ophelia traveled to the east picking up dust from the Sahara and smoke from large fires in Portugal. Retaining its tropical storm state farther northward than any system in the Atlantic, Ophelia carried the smoke and dust into Ireland and the UK.

Video at the link, or here’s the YouTube version. [APOD/Kottke]

NASA: “Satellites measured land and ocean life from space as early as the 1970s. But it wasn’t until the launch of the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) in 1997 that the space agency began what is now a continuous, global view of both land and ocean life. A new animation captures the entirety of this 20-year record, made possible by multiple satellites, compressing a decades-long view of life on Earth into a captivating few minutes.” Here’s a video about it:

Animations available for download here. Guardian coverage. [Benjamin Hennig]

At NASA’s Earth Observatory, before and after images of Puerto Rico’s nighttime lights illustrate the extent of power outages and infrastructure damage on the island. NASA has also produced a map of likely damaged areas of eastern Puerto Rico, based on before and after radar satellite interferometry and similar to the map they produced for the Mexican earthquake. At ground level, the CrowdRescue Puerto Rico Infrastructure Map displays crowdsourced reports of damage—downed power lines, bridge collapses, floods, mudslides and other incidents.