Sea Level Watcher Takes Flight - nasa.gov | Canada News Media
Connect with us

Science

Sea Level Watcher Takes Flight – nasa.gov

Published

 on


A joint U.S.-European satellite, built to monitor global sea levels, lifted off on a SpaceX Falcon 9 rocket from Vandenberg Air Force Base just after 9 a.m. Pacific Time on November 21, 2020. About the size of a small pickup truck, Sentinel-6 Michael Freilich will extend a nearly 30-year continuous dataset on sea surface height.

The satellite’s principal instrument is a radar altimeter, which monitors the height and shape of the ocean’s peaks and valleys—known to scientists as ocean surface topography. Radar altimeters continually send out pulses of radio waves (microwaves) that bounce off the surface of the ocean and reflect back toward the satellite. The instrument calculates the time it takes for the signal to return, while also tracking the precise location of the satellite in space. From this, scientists can derive the height of the sea surface directly underneath the satellite.

Sentinel-6 Michael Freilich will continue a sea level record that began in 1992 with the TOPEX/Poseidon satellite and continued with Jason-1 (2001), OSTM/Jason-2 (2008), and Jason-3 (2016). Together, these satellites have provided long-term, precise measurements of sea level height while tracking the rate at which our oceans are rising in response to global warming. Sentinel-6 Michael Freilich will eventually pass the baton to its twin, Sentinel-6B, scheduled for launch in 2025.

“Together, these satellites will let us keep measuring global sea levels for another full decade,” said Josh Willis, the NASA Project Scientist for the mission and an ocean scientist at NASA’s Jet Propulsion Laboratory. “It is the first time we have been able to launch one of these while its predecessor is still young. Jason-3 is still within its design life, and that is a big deal for us because to keep the record accurate when it gets handed off from one satellite to the next, we really need them overlap so we can cross-calibrate.”

Your browser does not support the video tag.

The time-lapse video above shows the plume of exhaust from the Falcon 9 in the 25 minutes after the rocket launched from California. The images were acquired with the Advanced Baseline Imager (band 2/red) on GOES-17. The satellite is operated by the National Oceanic and Atmospheric Administration (NOAA), and NASA helps develop and launch the GOES series.

The spacecraft is named in honor of Michael Freilich, the former director of NASA’s Earth Science Division and a leader in advancing ocean observations from space. Freilich retired in 2019 and passed away on August 5, 2020. His close family and friends attended the launch of the satellite that now carries his name.

“Michael was a tireless force in Earth sciences. Climate change and sea level rise know no national borders, and he championed international collaboration to confront the challenge,” said Josef Aschbacher, the director of Earth observation programmes for the European Space Agency (ESA). “It is fitting that a satellite in his name will continue the ‘gold standard’ of sea level measurements for the next half-decade.”

“The Earth is changing, and this satellite will help deepen our understanding of how,” said Karen St. Germain, director of NASA’s Earth Science Division. “Changing Earth processes are affecting sea level globally, but the impact on local communities varies widely. International collaboration is critical to both understanding these changes and informing coastal communities around the world.”

After arriving in orbit, the spacecraft separated from the rocket’s second stage and unfolded its twin sets of solar arrays. Ground controllers successfully acquired the satellite’s signal, and initial telemetry reports showed the spacecraft is in good health. Sentinel-6 Michael Freilich will now undergo a series of exhaustive checks and calibrations before it starts collecting science data in a few months.

[embedded content]

The initial orbit of Sentinel-6 Michael Freilich is about 20 kilometers (12 miles) lower than its ultimate operational orbit of 1,336 kilometers (830 miles). In about a month, the satellite will receive commands to raise its orbit, trailing Jason-3 by about 30 seconds. Mission scientists and engineers will then spend about a year cross-calibrating the data collected by the two satellites. Sentinel-6 Michael Freilich will then take over as the primary sea level satellite and Jason-3 will provide a supporting role until the end of its mission. Scientific instruments on both satellites will also make atmospheric measurements that can be used to complement climate models and help meteorologists make better weather forecasts.

Sentinel-6 Michael Freilich and Sentinel-6B compose the Sentinel-6/Jason-CS (Continuity of Service) mission developed in partnership with ESA, NASA, and NOAA. NASA JPL is contributing three science instruments to each Sentinel-6 satellite: the Advanced Microwave Radiometer for Climate, the Global Navigation Satellite System—Radio Occultation, and the Laser Retroreflector Array. NASA is also contributing launch services, ground systems and data support, and support for the U.S. component of the international Ocean Surface Topography Science Team.

To learn more about sea surface height and the long international collaboration to study it, read Taking a Measure of Sea Level Rise: Ocean Altimetry.

To learn more about Sentinel-6 Michael Freilich, visit the mission home pages at the European Space Agency, NASA, the European Union’s
Copernicus program, and EUMETSAT.

Looking for data related to sea level rise? The Sea Level Change Data Pathfinder on NASA’s Earthdata site highlights tools used by researchers to study ocean altimetry, including the Integrated Multi-Mission Ocean Altimeter Data for Climate Research.

NASA Earth Observatory video by Joshua Stevens, using GOES 17 data from NOAA and the National Centers for Environmental Information (NCEI). Photographs courtesy of SpaceX. Story assembled from NASA and ESA press releases by Mike Carlowicz.

Let’s block ads! (Why?)



Source link

Continue Reading

News

Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

Published

 on

 

More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

___

Follow AP’s climate coverage at https://apnews.com/hub/climate

___

Follow Seth Borenstein on Twitter at @borenbears

___

Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

Source link

Continue Reading

Science

‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

Published

 on

 

It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

The Canadian Press. All rights reserved.

Source link

Continue Reading

News

The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

Published

 on

 

TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

Source link

Continue Reading

Trending

Exit mobile version