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Forecasting Snow is a Difficult Task in Pyeongchang

February 21st, 2018 by Ivan Arias

Gangneung and Daewallyeong, the cities where the Winter Olympics are taking place, have a unique characteristic for precipitation. The cold and dry front from Siberia converges with the moist air of the Korean East Sea to produce stratiform clouds that occasionally precipitate over the PyeongChang province. This condition where the precipitation comes from the east is difficult for forecasters to predict. When the clouds are formed from the west due to low pressure, prediction is difficult because the ground-based radar’s sensing is limited due to the complex orography. Thus, no matter whether snow comes from east or west, it is always hard for meteorologists to forecast weather it in this area. Nevertheless, snow clouds in the region have a particular characteristic, they normally form around 2 kilometers over the sea level.

On February 13th, the D3R Radar from NASA which is located near PyeongChang captured a low elevation snow formation coming from the west which can be seen in the following images.

On the left is D3R RHI Reflectivity image at Ku frequency band, and on the right is D3R PPI Reflectivity image at Ku frequency band.

 

Compound Weather Radar Map of Korea by KMA.

However, no other operational radars from Korea were able to see the snow coming because of the complex relief where outdoor Olympic venues are located. The image below, taken from the KMA website, shows no snow around the PyeongChang region.

The D3R images allowed KMA staff to predict unexpected snow three hours before it started. Television screen captures taken on this day from the NBC Olympics broadcast (below) show snowfall during the cross country classic spring competition.

Photos of NBC live streaming the Winter Olympic Games.

In New Mexico, Land of Volcanoes

January 11th, 2018 by Jake Bleacher

On June 5, 2017, a convoy of vans and SUVs drove west from El Paso, Texas, and crossed into New Mexico, headed to a location about 20 miles southwest of Las Cruces. Leaving the pavement behind, we bumped along single-file on dirt roads, marking our way with a trail of GPS “breadcrumbs” and stopping occasionally to let the lagging vehicles catch up. Our destination: a geologist’s wonderland called the Potrillo volcanic field.

New Mexico is home to an impressive number and variety of volcanoes, spread over the state from top to bottom. Among them is the Potrillo volcanic field, a now-dormant region in the New Mexico portion of the Chihuahuan Desert. My team spent 10 days in June 2017 at Potrillo, visiting ancient craters and gently sloping shield volcanoes.

The Potrillo volcanic field. The volcanoes here are monogenetic, which means that when they were active, each one probably had a single eruption. These days, the Potrillo volcanoes are dormant. NASA Earth Observatory image by Jesse Allen.

Our team chose Potrillo because it combines the maar craters formed by explosive volcanism with the shield volcanoes formed by effusive volcanism. This makes it a perfect analog site for testing the kinds of instruments that future explorers might use to investigate volcanic areas on the Moon, Mars and other rocky planets or moons. We brought an array of instruments to map the topography of this terrain and to investigate the mineral composition and chemistry of the volcanic features here.

One of our destinations in the Potrillo volcanic field was the crater called Kilbourne Hole, shown in this fly-over footage taken by our unmanned aerial vehicle.  Music in this short video was provided by Killer Tracks. NASA/GSFC/UTEP.

I’m Jake Bleacher from NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and I led this trip. The group included planetary geologists from NASA Goddard; Stony Brook University in Stony Brook, New York; the University of Texas, El Paso; Johnson Space Center in Houston; and other institutions. This team is part of RIS4E, short for Remote, In Situ, and Synchrotron Studies for Science and Exploration, a five-year project led by Timothy Glotch of Stony Brook University. RIS4E is funded by NASA’s Solar System Exploration Research Virtual Institute, or SSERVI, which promotes collaboration linking science to human exploration.

Here, I’m pictured in the black leather cowboy hat I’ve worn on all field excursions for more than 15 years. NASA/GSFC

 

The Goddard Instrument Field Team, as a part of the RIS4E Project, explores Kilbourne Hole, a maar crater in the Potrillo volcanic field in New Mexico.NASA/GSFC

Helping me document the trip for NASA were Elizabeth Zubritsky, who worked with me on these blog entries, and two members of Goddard’s video team, David Ladd (producer) and Rob Andreoli (videographer).

The Commute to Work

October 19th, 2017 by Eric Lindstrom

Going to sea slows one down from the hectic sprint of modern city life and car travel.  We travel slowly (~12 mph) over the vast Pacific Ocean. It is a five-day journey to get to our “office” in the Inter-Tropical Convergence Zone (ITCZ).  The “work day” will change from 8 hours per day to 24 hours per day. There are no weekdays and weekends, only workdays and off-hours. As your blogger, I look into all the projects aboard ship and fill my day with writing, photographing action, and fact-finding for my reporting. I aim to provide a new blog four days-per-week (Tuesday-Friday). If needed I serve on a shift where extra hands are required.

A highlight of our departure from San Diego was being greeted by a large pod of small toothed-whales (porpoise/dolphin family). They seemed as curious of the ship as we were curious of them. We had slowed the ship as we passed the Coronado Island group (off northern Baja, Mexico) to deploy a 42-foot boom off the starboard bow. This is the support structure for Julian Schanze’s “salinity snake” that provides a “clean” intake of surface water outside the wake of the ship.  I imagine the whales had never seen such an operation before!

The 42-foot boom for the salinity snake.

The first two days at sea have been calm and sunny. This has been great for the newbies to get their sea legs. As far as I know no one has suffered severe sea sickness.

In the midst of our five-day commute we stop or slow down for training on occasion. Everyone needs to learn or refresh their knowledge on how instruments are deployed from the ship and safely recovered. This is the time to make sure all gear and personnel are ready for action. I will tell you more about the instruments and projects over the next month. Shipboard life is best when everyone is busy and every project is assisted to full success. During these initial days at sea there is much “cross-training,” you come to sea for one project, but you immediately train to assist on other projects.

Training class at the underway CTD winch.

As we move slowly south to the tropics we also have some small assignments to accomplish on behalf of the oceanographic community.  We will deploy some Argo floats along the 125W meridian. These temperature and salinity profiling devices join a global array of nearly 4000 floats that monitor the upper 2000m of the ocean.

We know our 24/7 work begins when we reach 11N, 125W and begin the process of recovering the NOAA mooring that has been there for the last 13 months.  There are three moorings in the SPURS-2 array and all will be recovered on this voyage. Generally, these moorings become teeming islands of life in the open ocean environment, attracting their own ecosystem of fish.  So, fishing gear will also be at the ready and we can expect tuna and mahi-mahi for dinner the day of a mooring recovery.

Finally, it looks like there will be some Halloween celebration aboard R/V Revelle.  The Captain has brought pumpkins for a carving contest. I hear that some people have costumes at the ready. I am sure some unique nautical and oceanographic twists can be brought to Halloween. We shall see. Never underestimate the imagination of people confined to a ship for five weeks!

Pumpkins at the ready for the Halloween pumpkin carving contest.

NAAMES-III Expedition: September 21, 2017

September 23rd, 2017 by Kristina Mojica

Muffin O’Clock

Through Einstein’s Theory of Relativity, it was discovered that time is not a static measurement, rather it is relative to the observer. Somewhat similarly, time becomes both integral and meaningless while on a boat, completely relative to the scientist’s schedule. Time is integral to the individual with their stopwatch waiting for the precise second in which they can stop their experiment. On the other hand, we have been on a ship for 22 days where weekends are only a fleeting memory and days of the week hold no meaning. How can one keep track of the day?

A fresh tray of blueberry muffins serve on board the R/V Atlantis

Food. While some view meal times solely as a source of nourishment, meals provide one of the only consistent ways we can keep track of our day on the ship. For example, at approximately 6:00 am every day, the cooks will place a freshly baked pastry of some kind in the galley. This is deemed muffin o’clock and you will often hear excited whispers and guesses around 5:30 a.m. on what could they be cooking up next. Biscotti, muffins, coffee cake, and scones are just a few of the impressive things the cooks on the Atlantis, Mark and Carl, have served at muffin o’clock. This is followed by breakfast at 7:30, lunch at 11:30, cheese o’clock at 3:00, and dinner + dessert at 5:30. For clarification, cheese o’clock is when cheeses, crackers, and sometimes smoked fish are placed in the galley where scientists and crew can feast together.

Food alone can not keep a ship full of sleep deprived scientists being productive. One of the most cherished traditions on the ship, in my humble opinion, is Coffee Club. I can not trade mark this, for there are a variety of coffee clubs on the ship that meet in a variety of locations and at various times. Science, politics, and religion are all fair game at these times of replenishment and all are welcome. When you see an individual with incredibly dark bags under their eyes but a little pep in their step, you can trust they just finished with coffee club and are about to be productive.

Living and working on a ship for 25 days straight is an incredible, rewarding, and often strange experience. Thankfully, the amazing scientists, crew, and cooks work together to create a fantastic environment so that exciting discoveries can be made in the air and sea.

P.S. If I didn’t make it clear enough, special thanks to Mark, Carl, and Tanzy for the amazing meals and clean-up!

Written by Savannah Lewis

Flying into Hurricane Harvey

August 27th, 2017 by Chris Ruf

I had the good fortune to join the crew of the NOAA P-3 “hurricane hunter” plane that flew into Harvey on 25 Aug 2017 shortly before it made landfall in Texas. We made six pairs of eyewall penetrations. The maximum surface level winds continued to grow with each successive one as we witnessed Harvey’s rapid intensification from a Cat 2 to Cat 4 hurricane. We were able to capture much of that dynamic transition, using continuous radar and radiometer remote sensing measurements plus frequent in situ measurements by dropsondes. These will be used to help calibrate and validate our measurements by CYGNSS, which have been ongoing since Harvey first started to develop earlier in the week. Following is a description of my experience that day.

Pre-flight briefing about an hour before take-off at 10:00 EDT.

The flight out to Harvey started ominously, with a detailed safety briefing before take-off for first timers like myself about things like the difference between what to do if we have to ditch in the ocean with more than 3 minutes of warning vs. less. The hurricane hunters have been flying for decades and have never had to ditch, so this gives you some idea of how thorough and detail oriented the crew is. After the safety briefing, the flight director mustered the full crew to discuss some last minute mission logistics and concluded with this: “Harvey is currently a Cat 2 hurricane and is expected to undergo RI (rapid intensification) while we are in the air, then head for landfall tonight near a major population center. Days like today are why we are here. Now let’s go do our jobs.” We were “wheels up” 15 minutes later at 10:00 EDT.

Me with two of the CYGNSS science team members, Dr. Paul Chang (left) and Dr. Zorana Jelenak (right), who were airborne mission scientists on the flight.

The two hour ferry flight from Florida across the Gulf of Mexico wasn’t much different from any commercial flight. But as we approached Harvey’s outer rain bands, things changed. Everyone strapped into their seat with four-point restraints across their chest and lap. Headsets were on and a steady chatter began between the flight director and the crew operating the various remote sensing equipment and dropsondes. A real time display from one of the radars showed the rain distribution within a 200 mile radius around us. Heavy rain spiraled out in bands from a bright circle to the south of us at the edge of the image. The plane banked to the south and headed toward that circle – the eyewall. The flight became more turbulent as we approached it. Occasionally, the bottom would drop out from under the plane and I would find myself lifted up off my seat, held down only by the straps. The flight director called it “sporty plus”. The worst of the turbulence occurred out in the spiral rain bands. Flying conditions became smoother as we approached the eyewall, but the skies grew progressively darker and, flying at 8000’ altitude and well below the freezing level, heavy rain streaked across the windows. A second real time display, from a microwave radiometer, showed the surface wind speed directly below the plane. It had been increasing steadily since we headed south into the inner core of the storm. Then we entered the eyewall. The rain became even more intense, the surface wind spiked above 51 m/s (~115 mph), and the skies darkened even more. Then, in the next minute, the interior of the plane grew suddenly brighter and the turbulence disappeared. Looking out the window, I could see the ocean below us and blue skies above. The radiometer showed that the surface wind speed had dropped below 10 m/s and the radar image drew a bright circle of intense rain all around us with nothing in the middle. We were in the eye of Harvey.

A visible image taken by the GOES satellite at 15:15 CDT as we were flying through the eye.

Looking out the window at 8000’ in the eye of Harvey (photo by Brad Klotz).

Over the next few hours, we conducted a total of six pairs of eyewall penetrations, each time circling to a new azimuth angle before entering the eye again in order to map out as complete an image of the storm structure as possible. With each successive penetration, the maximum winds encountered in the eyewall kept growing. We were experiencing firsthand Harvey’s rapid intensification phase as it strengthened all around us.

Screen captures of the flight line of the mission: (top) As we were ferrying out to the storm, when we got our first look at the eye (toward the south) with the airplane’s radar. (next) Starting our first (north-to-south) eyewall penetration. (next) Lining up for our second (east-to-west) penetration. (bottom) After our last (sixth) penetration, as we prepare to ferry back to FL.

Our measurements were radioed back to the National Hurricane Center in Miami as they were made, to be fed into their forecast models and to be forwarded to the media and emergency responders to let them know what Harvey had become and to help them prepare for what was headed toward Texas. Finally, as our fuel began to run low, we left the storm and returned back across the Gulf to our base at the NOAA Airborne Operations Center in Lakeland, FL. Minutes before landing, we received confirmation from the NHC that Harvey had been officially classified as a Cat 4 hurricane.

The P-3 right after we landed. Lots of hurricane remote sensors are visible on the wing and underside of the fuselage. She took very good care of us.

Notes from the Field