Ice, ocean, and glacier change in northern Greenland

Posted on April 7, 2022 by | Leave a comment

Steffen Olsen is a Danish physical oceanographer with a skill to present beauty to an artist like my wife and a scientist like me. Three days ago he posted a photo on Twitter with these words

“Local hunters from Qaanaaq navigating our CTD system in the frozen ice mélange in front of Tracy Galcier 66W 77N to measure the ocean below. Heat loss to melting of glacial ice leaves the ocean at sub-zero temperatures down to 400m @arctic_passion @dmidk @ruth_mottram“

Photo: Dogsled from Qaanaaq near the northern edge of Tracy Gletscher in Inglefield Fjord April 2022. [Credit: Dr. Steffen Olsen, Danish Meteorological Institute.]

Steffen’s photo shows his study area, research platform, and mode of transportation. There is a glacier in the background between the rocks on the left (north) and unseen mountains to the right (south). Equally unseen is the ocean under all this crushed and broken and piled up sea ice covered by fresh snow. We see tracks of people walking to the vantage point from where the photo is taken. The dogs rest on a small patch of level sea ice perhaps 3-5 feet (1 to 1.5 meters) thick.

There are boxes on the sled that contain gear to drill through the sea ice and then to send a probe down towards the ocean bottom to measure ocean temperature, saltiness, and oxygen during its decent. I did similar work with a snowmobile in 2017 based at Thule Air Base for 6 weeks. Steffen and I work together on such data. He collected these every year since 2011 both adjacent to Tracy Gletscher and along most of the ~120 km long and ~1000 meter deep fjord. I am grateful to Steffen to share this photo: It helps me to focus on my passions rather than my outrage at soldiers and leaders of the Russian Federation in their war to destroy Ukraine and its people building a free, vibrant, and democratic country for themselves. There is more, but I stop here now.

Let me start with a map of where in Greenland the photo was taken and where Steffen collected his data each since 2011. The red star in the insert top-right shows the location of the map between Canada and Greenland. I color ocean bottom depths in blue shades and land heights in green, yellow, and brown shades. The glacier in Steffen’s photo is at the north-eastern end of Inglefield Fjord where I placed the label Tracy. The label Qaanaaq shows where about 650 Inughuit live along the coast near the center of the fjord. It probaby took the dogs about 2-3 days to travel with their cargo from Qaanaaq to Tracy Gletscher. Red dots are stations served by a Danish Navy ship in the summer of 2015, but I here only talk about the blue dots.

Figure: Map of the study area with ocean sampling stations in Inglefield Fjord (blue dots) and adjacent northern Baffin Bay. [Unpublished own work.]

The blue dots are stations where Steffen and his companions drilled through the sea ice in 2018. Note that some of those ocean stations appear on land. This cannot be, but the glacier has retreated between the time the topographic data was collected and 2018 when Steffen collected the ocean data. Three LandSat satellite images below show how the glacier changed from 1973 to July and August of 2021. Icebergs are visible, too. A citizen scientist with the handle “Espen” at the Arctic Sea Ice Forum extracted these satellite photos from public U.S. databases. He is part of an online international community of Greenland and sea ice enthusiasts who posts at this forum for over a decade making daily discovers. These are people with regular jobs that in their spare time post satellite imagery and open data they found which they share openly often with insightful interpretations. It is citizen science at its very best. I go there often to read, ask, and learn. I even met a prominent member once for lunch when visiting Copenhagen on my way to Greenland. He gifted me LandSat imagery of my favorite glaciers printed on cloth that I framed for its scientific and artistic beauty. Thank you, Espen 😉

Gallery: Space photography (LandSat) of glaciers terminating from the Greenland ice sheet in Inglefield Fjord in 1973 (right), July 2021 (center), and August 2021 showing the retreat of Tracy but not Heilprin Gletscher. [Credit: Espen Olsen at Arctic Sea Ice Forum.]

So how does the ocean below all this ice next to a glacier look? Well, lets look at a set of station from Qaanaaq to Tracy Gletscher that shows how temperature, salinity, and oxygen of the water changes both with depth and along the fjord. We always find very cold, somewhat fresher, and highly oxygenated water near the ocean surface about 40 m (near glacier) to 100 m (near Qaanaaq) below the sea ice and warmer, saltier, and less oxygenated water below with a temperature maximum of 1 degree Celsius near 300 m depth. It is this warm water that melts the adjacent glacier. As Dr. Olsen says “… Heat loss to melting of glacial ice leaves the ocean at sub-zero temperatures …” In other words, the deeper waters 1. enter the fjord at temperatures above zero degrees Centigrade, 2. reach the glacier, 3. cool down as they melt the glacier, and 4. leave the fjord at temperatures below zero degrees Centigrade. This is why the two stations near the glacier show slightly fresher and cooler waters between 300 and 500 m depth. This water contains the glacial melt. The section represents the 10 year average from 2011 through 2020.

Figure: Section of salinity (bottom), temperature (center), and dissolved oxygen (top) along Inglefield Fjord as an average of data collected annually between 2011 and 2020. [Unpublished own work.]

Earlier this year I tried to visit Copenhagen to finish this work that places this emerging story into both a historical and spatial context, but Covid restrictions derailed this and other plans. Nevertheless, have excellent data from 1928 when this fjord was first surveyed by Danish oceanographers. At that time the waters had dramatically different temperatures (much colder) and salinities (a little fresher) both inside the fjord and in Baffin Bay adjacent to it. The changes are probably related to a much changed sea ice cover and perhaps ocean circulation that relates how the winds impact the ocean with and without sea ice. For the 1979 to present satellite record, we can quantify how much sea ice covers both the fjord and adjacent ocean. I made the graph below last week from 14073 almost daily satellite images whose data the U.S. National Snow and Ice Data Center distributes freely. I show annual averages for each of the 42 years that these SSM/I satellites have been measuring sea areal coverage from space.

Figure: Annual averages of sea ice cover 1979 through 2021 with linear trend lines for two 21-year subsets (blue) and the entire 42-year record (red). [Unpublished own work.]

Before the year 2000 the sea ice cover fluctuated between 26,000 and 39,000 km2 and if one for how these changes are trending between 1979 and 2002, one finds a slight increase in the blue line, however, this increase is not significantly different from zero at a high 95% level of confidence. For the second period after 2002, the ice covered area fluctuates much less, from about 22,000 to 28,000 km2 and the trend line in blue now indicates decreasing sea ice cover. As before, however, this blue trend line is no different from zero at the same high level of confidence. We also notice that there is a red trend line that I derive from using all 42 years of data. This line is very different and statistically significant, but it does not quiet do justice to the almost step-like change that appears to happen around 2000 through 2005. What happened then? I do not know, yet, but this is the fun of doing science: There is always more to discover. The sea ice cover in northern Greenland does not always follow a straight line. This is not different from our climate or life. Expect the unexpected, adjust, and keep moving. Or in Dr. Olsen’s words:

“… you have a number of years where conditions don’t follow the more linear track of (predicted) scenarios,” explained Dr. Olsen. “A warming tendency can be reversed for some years, for example.” [From https://phys.org, Oct.-13, 2021]

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Waves Across the Pacific

Posted on January 11, 2021 by | 2 comments

Claudia Schreier is a sophomore at the University of Delaware. She majors in Chemical Engineering with a minor in Marine Sciences. Ms. Schreier’s essay emerged from an assignment in an undergraduate “Introduction to Ocean Science” class taught by Drs. K. Billups and A. Muenchow in the fall of 2020. ~A. Muenchow, Editor

The 1967 documentary “Waves Across the Pacific” highlights some of the first uses of high-tech measuring tools and novel techniques to discover how waves move across the Pacific Ocean. Dr. Walter Munk and his research team studied how wave energy from storms off Antarctica is lost as waves move across the equator towards Alaska. This was the first time that anyone collected and reported data for wave processes on a global scale.

Dr. Munk in 1963 (UC San Diego Library)

The vessel that the team used for this expedition was fascinating; it is called FLIP, and it is a mobile floating instrument platform standing 355 feet tall, providing both the space and stability for the laboratory and its equipment. Waves originating from Antarctica reached New Zealand, and then moved farther in every direction within the Pacific Ocean. Recording stations were located in New Zealand, Samoa, Palmyra (an uninhabited equatorial atoll), Hawaii, and Alaska. In the North Pacific without suitable islands between Hawaii and Alaska, FLIP was used for wave measurements. Dr. Munk’s headquarters and central wave station for the experiment was in Honolulu, Hawaii.

The Floating Instrument Platform (Smithsonian Ocean)

Dr. Munk originally hypothesized that most of the wave energy coming from Antarctica would be scattered in the equatorial Trade Wind regions, therefore preventing most Antarctic waves from reaching the North Pacific. However, the data revealed little energy loss as the waves crossed the equator. The team discovered, though, that wave attenuation, or the loss of energy, results from interactions of waves from the same storm near its generation region off Antarctica only. Furthermore, the interactions between such waves weakened as they traveled away from the generation region through wave dispersion. This means that waves of different frequencies can travel at different speeds, therefore sorting them, because long waves move faster than shorter ones. Because of this data and new understanding, Dr. Munk could predict surfing conditions in Hawaii from prior observations off Samoa! The data and methodology from this experiment became the cornerstone of many subsequent studies to predict waves.

Recording stations from the study (Munk 2013)

The documentary film captured not only research methods but also life in the 1960s. I appreciated this look back in time, and it got me thinking about women in ocean sciences. In the film, all of the research scientists were men, and no women participated in the project whatsoever. The scientific community has come a long way since then, with more women participating and leading in both science and technology, as well as leading their fields, than ever before. The film helped me to realize that my interest in science and the opportunities to pursue a career within it has been aided by the efforts of countless women who have come before me.

This documentary also made me hopeful in a curious way that I did not expect from a marine science documentary. Dr. Munk was unsure about many things in this study, including the novel technology, remote measuring locations, and even the validity of the experiment itself. Amassing over 10 million data points, he found both the purpose and the results he was seeking for this research in the face of uncertainty. This documentary gave me a fresh take on ocean sciences, and it does more than just explain the brilliant research done in the 1960s: there are still many things we do not know about the world, but with the spirit and drive of Dr. Munk, there is no limit to what can be discovered.

A link to the film: https://waltermunkfoundation.org/uncategorized/waves-across-the-pacific/

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Posted in History, Oceanography, waves

Election Work during a Pandemic

Posted on September 17, 2020 by | Leave a comment

Elections are messy, but patterns emerge. Elections have consequences, but people learn. Elections make news, but do we all know how they work? I did not and thus decided to learn. I served as a sworn-in Election Clerk in the State of Delaware this week to collect first-hand experiences. I wanted to decide for myself rather than just “believe” or “dismiss” abundant disinformation propagated by Russian and American troll farms on social media. I wanted to answer for myself, if the American election system is safe, fair, and secure. My answer is a resounding yes for New Castle County, Delaware.

My badge for the Sept,-15, 2020 Closed Primary Election in New Castle County, DE, USA.

Any registered voter can apply to serve at a polling station as an Election Clerk, Judge, or Inspector:

The State of Delaware needs more than 4,500 registered voters to work in polling places for the General Election. This is a unique opportunity to serve your community by participating in the electoral process!

https://elections.delaware.gov/information/electionofficers.shtml

Pay comes to about $10 per hour for a 19 hour commitment. Students enrolled at a university in Delaware and local High School students older than 16 can apply as well. Within a week of mailing my application I was assigned a date and location for both a 4-hour training session and an election. I worried about the many, usually elderly election workers during our current Covid-19 pandemic. I took a calculated risk, but our democratic system by the People for the People requires the People to actually run the elections. Random citizens working the polls on Election Day are one check on State Governments who organize the elections.

Election Day started at 6 am to set-up computers, machines, and voter information in the gym of a local Elementary School. The first voter appeared at 7 am sharp while the last voter left shortly after 8pm. I left the school at 9 pm after votes were tallied, results were signed by each of poll workers and posted at the school. Multiple signed copies of votes and results were delivered by different people to different officials and offices. This includes both electronic and paper copies of each vote. I was home at 9:15 pm, exhausted, sore, and tired. A Samuel Smith’s Imperial Stout helped me to end the day happy, proud, content, and with many stories to share.

The best part was a wonderful, random, fun, and most diverse group of 11 poll workers. We ranged in age from 21 to 75 (or so), almost evenly split male/female, black/white, college/non-college, etc. and all with a refreshing sense of humor and purpose. One of us was a pastor, a postal worker, a home-maker, two professors, a school psychologist, a teacher, and we had at least three grand-parents. About 540 people came in to vote, only one person tried (and failed) to cheat by voting twice. He tried to vote in-person after he had mailed-in his absentee ballot which the State received already. He was politely told to leave which he did quietly. Perhaps he just tried to test the system, or he just forgot that he mailed his ballot, or he just listened to a paranoid and ignorant politician who told people to vote early by mail and then try to vote again in person. Either way, nobody voted twice.

Example of a mask violating Delaware’s Electioneering Laws, if worn inside a polling place.

We only had 3-4 people who tried to violate State Electioneering Laws (Del. Code Ann. tit. 15, §4942(a); (d)) by displaying partisan buttons, masks, hats, or t-shirts inside the polling place. This is illegal in Delaware and elsewhere; so please do not bring Biden/Harris or Trump/Pence buttons or similar partisan apparel or clothing to the the polling place. The “Electioneering” link is from the bipartisan National Association of Secretaries of State. Interestingly, all three “electioneers” were angry, white, male, 45-60 years old, and affiliated with the same party. They represented less than 2% of that party, but the three men succeeded in causing drama, emotional turmoil, and disruptions both inside the polling place and afterwards. I will fight for them to express their views as guaranteed by the U.S. Constitution, but their freedom of speech is limited inside the 50 feet diameter of the polling place during the 13 hours that people vote there. Several U.S. Supreme Court decisions back this view.

Only one person did not wear a mask, but this was my fault. He entered with a mask that carried in large letters a partisan political statement not allowed inside the polling place. When called on this by an Election Clerk he got angry and started to argue, but he was happy when I told him that he did not have to wear as mask that he promptly took off. [It was my mistake to tell him that not wearing a mask does not disqualify him from voting.] I asked to handle this person and borrowed the crutches of our oldest poll worker (with her permission) to use as a “teaching prop” of the 6 feet distance that I needed. He co-operated nicely and I thanked him for his important participation in an important process.

A more positive experience for me was to see how diverse my local community is. People of all colors, genders, ages, handicaps (both physical and mental) gave me a new perspective on who lives in the same town with me. I noticed an especially happy and celebratory atmosphere of the many black women of all ages who often came with their teenage sons and daughters to vote also. Many couples had different party affiliations and got along just fine. Kids came, too, as their parents voted and show them how its done. There is Hope and Strength in Diversity.

Stained glass window by Dragonfly Leathrum

As a skilled physical scientist and computer geek, I conclude that it is almost impossible to “cheat” on the actual vote both for absentee (often called mail-in) or in-person ballots. I also conclude that Russian and American trolls and politicians try to suppress, manipulate, and disrupt the vote by spreading lies and disinformation to create doubt and confusion. The threat becomes real, if we the People believe and spread such lies. Our voting system has evolved over more than 200 years. It is secure as (a) both electronic and paper copies of each ballot exist; (b) all containers, machines, and access points are sealed, documented, and traced; (c) custody of all materials is transparent with multiple checks; and (d) it is random People like you and me who run the nitty-gritty of elections. The process is transparent and open to anyone willing to spent 4 hours of training and 14-15 hours on Election Day.

P.S.: I had myself tested for Covid-19 this morning. The sore throat and cough probably resulted from talking to more people than I have seen the last 7 months and breathing through a mask for 15 hours straight.

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Posted in covid-19, Election, Uncategorized, Uncertainty

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Rotations, Spin, and People

Posted on August 23, 2020 by | Leave a comment

I hate to rotate. It makes me sick. And yet, every day I spin at 800 miles per hour, because living on a spinning earth does this to me. Why does the earth spin at all? [CalTech answer.] Did it always spin the way it does now? [No.] Could it spin in the other direction that would make the sun rise above the horizon in the West rather than the East? [No.] If not, why not? [Not sure yet.] I am pondering these questions as I will teach my first undergraduate class in ten days:

I plan to introduce how oceans and atmospheres circulate to distribute heat, water, and “stuff” like food and plastics across the globe. There is lots of rotation, lots of angular momentum, lots of torque and I am unsure, if a text book and lecture via Zoom will make much sense. So, today I discovered several fun and smart and insightful videos that I may even pose to my students as Homework or Exam questions 😉

The first set of videos I discovered today is Derek Muller’s Veritasium channel on YouTube. He covers a range of physics, math, and even biology topics, but I here focus on his wing nut problem. He entertains by explaining a strange and even bizarre observation made in space some 30 years ago. A Russian engineering astronaut noticed a rotating wing nut change its rotational axis repeatedly. Russia kept the observation top secret for over 10 years for reasons not entirely clear, but here is a modern attempt to explain what happened. It also applies to how tennis rackets rotate:

Now this reminded me of a problem that I encountered during my third year studying physics in Germany. I never solved or understood this so-called spinning-hard-boiled-egg problem that the Physics Girl describes so well. Her real name is Dianne Cowern and I use her videos in my graduate statistics class where her voice and physics shatters wine glasses via resonance. Today I discovered many more of her PBS Digital videos that all are filled with fun, beauty, and smart explanations. She plays with vortices in air and water and in between.

Now how does this relate to oceanography and meteorology? Well, we all live somewhere on the spinning top or egg or peanut that we call earth. Gravity keeps us grounded, but rotating objects can do strange things as the above two videos show. And when rotation becomes important we are not just dealing with linear momentum, but also angular momentum. When rotation becomes important, we must consider torques that generate angular momentum in ways similar to how forces generate linear momentum.

Rotation adds a strong and often counter-intuitive element because unlike a force that accelerates a car in the same direction that the force is applied, a force applied to a rotating system generates a torque perpendicular to both the force and the direction to the rotational axis. This can be confusing and one has to either watch the movies or go through advanced vector calculus. Furthermore, a rotating sphere acts differently than a rotating spheroid which acts differently from a rotating triaxial spheriod. Our peanut earth is the latter and thus has at least three axes of orientation (a and b and c) that all have different kinetic energy and angular momentum states. This makes for wobbly rotations which are sensitive to changes in both force balances and the distribution of masses like ice and water that can move to different locations at different times and stay there for a while.

For a perfect sphere three perpendicular lines from the center to the surface all have the same distance a (top) while for a spheriod only two of the three perpendicular lines have the same distance from the center (bottom right). If all three perpendiculars are different then we have something called a triaxial spheroid [Adapted from WikiPedia].

And how does this relate to climate science and my beloved glaciers in Greenland? Well, there is the “global wobbling” that caused ice ages and warm periods as the earth’s principal axis or rotation changes or wobbles. The “global wobble” was discussed in hilarious way a few years ago by the United States House of Representative’s “Committee on Science, Space, and Technology.” Closing this essay, I let Jon Steward of the Comedy Channel speak and hope you find his commentary and live experiment as funny as I do:

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Posted in Global Warming, Greenland, Oceanography, Uncategorized

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Data Obsessions while in Self-Quarantine

Posted on April 2, 2020 by | 1 comment

I sit in my home office looking into a garden which explodes in yellow from the forsythia with splashes of pink from the camellias. Both flourish after a large shading cherry tree fell down a few years ago. The tree stump is covered by moss and provides a natural border. My native American Flame azaleas (Rhododendron calendulaceum) now stand 8 feet tall in front after I planted them in 2001 as 3 inch sticks. They are the pride of my garden along with Piedmont, Sweet, Okonee, and Plum azaleas all purchased from Callaway Gardens in Georgia. They grow well, because I correctly predicted that the warmer climate zones of Georgia would move northward towards Delaware. Here are the azaleas in blooms in early May or four weeks from now:

American native azaleas blooming in my garden in April and May.

These are distractions, because I need to process and analyze ocean velocity data off Greenland. My student from South Korea rightfully expects numbers that she can work with for her Masters degree. We plan to meet via Zoom video call every Friday and Wednesday. She is ordered to stay at home in Maryland while I am ordered to stay at home in Delaware. We also meet Monday and Wednesday evenings when I teach “Waves” via Zoom to eight University of Delaware graduate students from China, South Korea, Thailand, and the USA. Our topic yesterday was the waves in the wakes of a ship or a duck or an island. To me physics are as beautiful as are the flowers in my garden:

Now these are the things that I should work on during my self-quarantine, but I am obsessed and distracted with new data. The Johns Hopkins University in Baltimore, MD distributes data on the number of people who were diagnosed with Covid-19, who died of it, and who have recovered. While it is easy to access their excellent data displays as global health authorities report them, the actual raw digital data files are accessible at

https://github.com/CSSEGISandData/COVID-19

These data require computer programming and data handling skills that a well trained physical ocean, climate, or data scientist masters. The raw data, however, do not tell a story, because it just looks like gibberish,

but there is a most orderly system to this madness. With 143 lines of computer code (one C-shell and two awk scripts) I convert these data into a single graph to tell a story:

First, I focus only on the number of people who have died, because I consider this the most reliable (albeit morbid and depressing) estimate of how the virus is spreading.

Second, I present the number of people who died relative to the population. It hardly seems fair to compare the numbers from the USA with 327 million people to those of Malta with only 0.5 million people. The technical term is “normalization,” that is, all numbers are relative to 1 Million people. So, 5 dead in Malta give 10 dead per million. The same 10 dead per million correspond to 3270 dead Americans. This way I am comparing apples to apples as opposed to Americans to Maltese.

Third, I want to compare the spread of the pandemic over time on different continents, different countries, different states, and different cities. This requires to time-shift countries hit by the virus earlier than others. In the above graph, for example, I moved the curve for Italy 14-days forward and that of Spain 6-days forward relative to all other places listed.

Fourth, I am most interested in New York State (population 20 million), because it contains New York City (population 8 million) and, I believe, it gives Americans a good idea what is coming. Furthermore, I believe, that the Government of New York State is a little more efficient, smart, and forward-thinking than many other government entities. It also has resources not necessarily available to less affluent communities.

The curve for New York State initially (until Mar.-25) followed the trajectory of Italy 14 days earlier, but then it switched over to the steeper trajectory of Spain 6 days earlier. Notice that Italy’s curve has a flatter trajectory than the steep curve of Spain and New York State. From Mar.-28 to Mar.-31 the New York curve was almost exactly that of Spain 6 days ago, but yesterday, the number of people dying in New York grew even faster than those in Spain or Italy ever did. This is scary stuff.

Yesterday, New York State had about 111 dead per million people. While this is still less than the 180 dead per million people that both Italy and Spain had yesterday, it may take only 4-5 additional days for New York State to reach those numbers also, but I still do not know what these numbers mean. I do not “feel” them. So I try to compare them to other causes of death such as people getting killed every month in (a) car accidents (9 per million) or (b) gun violence (8 per million) or (c) cancer (126 per million). These references help me to visualize the scale and impact of this pandemic.

So, while Covid-19 has killed about as many people in the US the last 4 weeks as people died in car accidents, in New York State the number of Covid-19 dead is about to exceed those who died of cancer in this same period. The hardest hit place in the US, however, is not New York City (160 dead per million), but New Orleans (295 dead per million). The County or Parish of New Orleans, Louisiana has about 400,000 people or a little less than New Castle County in Delaware where I live, but New Orleans has 115 dead compared to 5 in New Castle County (9 dead per million).

There are a few bright spots and I want to close on those. Los Angeles (7 dead per million) and California (5 dead per million) are doing remarkable well as does Germany (11 dead per million). Despite physical separations from others, I feel closer to friends, family, and neighbors both overseas and across the street. With more than 10 feet distance we have impromptu get-togethers between the door and the end of the driveway of 4 different households. I am happy to know that my neighbor Joyce from Kenya is safe back home living quarantined across the street with her African friends from Mali. She runs Water for Life which is a small non-profit that provides clean drinking water for rural communities in Kenya. It makes me happy to know her as a neighbor across the street.

And then there are the true warriors who fight this virus while endangering themselves to help others. Here is a nurse from Spain whose photo at work I took from her Twitter feed. We are all surrounded by wonderful and beautiful people.

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Posted in Computing, health, Uncertainty

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