Glaciers, Geocaching, and Greenland Goals

I thought it silly when my wife suggested to go geocaching with her. She told me it was to hunt for treasures and as a professor of physical ocean science and engineering this was not for me. But my wife is persistent, I am curious, and when she explained that a GPS, hiking, and computer mapping was involved, I gave it a try and have been hooked ever since. My first geocaching hiking trip took place on Anacortes Island, Washington in 2013 where our youngest son then lived. Here we are walking past rock carved 10,000 years ago by a tiny glacier at N 48° 29.498 W 122° 41.799 N that discharged ice into Puget Sound:

Glacier carved outcrop in Washington Park, Anacortes Island, WA.

Glacier carved outcrop in Washington Park, Anacortes Island, WA.

Since this first geocaching trip, I have found more than 200 geocaches in places small and remote and places large and urban. The treasure is in the walking and trying to find a path towards a destination, but the destination is secondary as many discoveries are made along the way.

This often happens in science also. One needs to know a destination, have a goal, formulate a hypothesis, but much science, learning, and discovering happens along the path towards that goal. With a GPS the destination is easy, it is a fixed point on earth, but it is harder in science. It can be useful to roam widely, but a set of intermediate goals can help to stay focused. For example, I want to understand how Greenland will change as we warm the earth. That’s a big question with impacts on floods in Europe, storms in the Americas, and rising sea level everywhere. This is a 100-year problem that many people work on; so my personal goal is to focus on how the oceans melt glaciers from below. This is a 10-year problem. It is a step towards the larger goal, but 10 years is still long even though I work with people in Germany, Canada, Denmark, England, Sweden, and Norway:

View to the south on the climb down from Tromsdalstinen.

View to the south on the decent from Tromsdalstinen on a geocaching trip in 2014 out of Tromso, Norway.

The photo above was made during one of my geocaching trip in northern Norway. Three physical oceanographers had gotten off the ship after they deployed ocean current measuring devices off eastern Greenland near a larger ice sheet. The experiment was designed to measure the ocean heat and its movement towards two large outlet glaciers. One has a wide and stable floating ice shelf, Nioghalvfjerdsfjorden (79N Glacier) while Zachariae Isstrom a few miles south lost its wide, long, and apparently unstable ice shelf that still shows in this 2002 image:

North-east Greenland: 79N Glacier and Zachariae Isstrom in 2002.

North-East Greenland in 2002 when both 79N Glacier (near 79 30′) and Zachariae Isstrom (near 79 00′) had extensive ice shelves (black areas are open ocean).

It puzzles me how two adjacent glaciers can and do behave so differently. If we understand how Greenland is melting, then we should explain the difference convincingly, but I am still looking for people who can. Lots of theories, lots of ideas, and lots of modeling, but there are not many observations to make the skimpy and often contradictory evidence convincing. And this finally leads me to my last point and the goal that I set for myself for the next 5-10 years:

I like to measure the ocean, the ice, and the air above and below floating glaciers via a small network of sensors. Now that two large ice islands spawned at Petermann Gletscher in 2010 and 2012, I believe that the remaining ice shelf will stay largely put for the next few years, that is, move at 1 km per year towards Nares Strait:

Petermann Gletscher through calving events. White lines show ICESat tracks; red (ambient ice shelf) and blue (central channel) show repeat-track airborne surveys.

Petermann Gletscher through calving events. White lines show ICESat tracks; red (ambient ice shelf) and blue (central channel) show repeat-track airborne surveys.

The hardest part in reaching this goal is to get measurements from under the 200-600 meter thick ice. This requires holes drilled through the glacier, it requires ocean sensors to be lowered into the water below the glacier, and it requires connections to relay data back to the surface at all hours for many year. I  perhaps have a first chance towards this goal when the Swedish icebreaker Oden will work for a month in Petermann Fjord this year. People from the British Antarctic Survey will be aboard and they plan to drill holes for other scientific purposes. When they are done, the holes freeze over, unless someone (me, me, me, please, pretty, pretty please) has instruments to put in there. I just word that I will be aboard the ship as well and I am feverishly working towards this goal with much help from others. More on this in later posts. All science is a group effort.

I close with a photo to show how the ice-covered ocean of Petermann Gletscher looks during the polar day. Would it not be great to know the temperature of the water below and the air above this more than 200 meter thick glacier ice at all times posted for everyone to use with an internet connection?

March-24, 2010 view of Petermann Glacier from NASA's DC-8 aircraft. Photo credit goes to Michael Studinger of NASA's IceBridge program.

March-24, 2010 view of Petermann Glacier from NASA’s DC-8 aircraft. Photo credit goes to Michael Studinger of NASA’s IceBridge program.

Freedom of Expression and Islam

The bullets and hatred that today killed 10 journalists of the French publication Charlie-Hedbo and two police men were directed at all of us:

Charlie-Hedbo Jan.-7, 2015.

Charlie-Hedbo Jan.-7, 2015.

Let us not forget in our grief, rage, and sadness, that many men, women, and children of the Islāmic faith are the main victims of this particular murderous strand of cowardly religious fanaticism that fears reading, writing, and arithmetic as practiced by diverse, tolerant, and educated women and men. And children.

Jyllands-Posten, Sept.-30, 2005.

Jyllands-Posten, Denmark, Sept.-30, 2005.

Children like Malala Yousafzai deserve a brighter future than the darkness that is promised and practiced by the Taliban, Islāmic State, and Al-Qaeda.

Malala Yousafzai, Nobel Peace Prize winner 2014.

Malala Yousafzai, Nobel Peace Prize winner 2014.

Failed men tried to silence Malala as an unarmed 14-year old girl the same way that today they tried to silence the unarmed French journalist. Their method, bullets to the head, failed then, failed today, and will fail in the future.

The real Islam of scholarship, tolerance, and equality is on display in this interview of Malala Yousafzai with Jon Steward:

Changing Weather, Climate, and Drifting Arctic Ocean Sensors

Three people died in Buffalo, New York yesterday shoveling snow that arrived from the Arctic north. The snow was caused by a southward swing of air from the polar vortex that is all wobbly with large meanders extending far south over eastern North-America where I live. Physics deep below the thinly ice-covered Arctic Ocean hold a key on why we experience the Arctic cold from 2000 km north and not the Atlantic warmth from 100 km east.

A wobbly jet stream that separates cold Arctic air from warmer mid-latitude air. Note the strong gradients over eastern North America. [From wxmaps.org]

A wobbly jet stream on Nov.-19, 2014 that separates cold Arctic air from warmer mid-latitude air. Note the strong differences over eastern North America and how balmy Europe, Russia, and Alaska are. [From wxmaps.org]

The Arctic Ocean holds so much heat that it can melt all the ice within days. The heat arrives from the Atlantic Ocean that moves warm water along northern Norway and western Spitsbergen where the ocean is ice-free despite freezing air temperatures even during the months of total darkness during the polar night. As this heat moves counter-clockwise around the Arctic Ocean to the north of Siberia and Alaska, it subducts, that is, it is covered by cold water that floats above the warm Atlantic water.

North-Atlantic Drift Current turning into the Norwegian Current that brigs warm Atlantic waters into the Arctic Ocean to the north of Norway and Spitsbergen. [Credits: Ruther Curry of WHOI and Cecilie Mauritzen of Norwegian] Meteorological Institute]

North-Atlantic Drift Current turning into the Norwegian Current that brigs warm Atlantic waters into the Arctic Ocean to the north of Norway and Spitsbergen. [Credits: Ruther Curry of WHOI and Cecilie Mauritzen of Norwegian] Meteorological Institute]

But wait a minute, how can this be? We all learn in school that warm air rises because it is less dense. We all know that oil floats on water, because it is less dense. Well, the warm Atlantic water is also salty, very salty, while the colder waters that cover it up are fresher, because many larger Siberian rivers enter the Arctic Ocean, ice melted the previous summer, and fresher Pacific waters enter also via Bering Strait. So, the saltier and more dense Atlantic water sinks below the surface and a colder fresher layer of water above it acts as a insolation blanket that limits the amount of ocean heat in contact with the ice above. Without this blanket, there would be no ice in the Arctic Ocean and the climate everywhere on earth would change because the ocean circulation would change also in an ice-free Arctic Ocean, but this is unlikely to happen anytime soon.

A single profile of temperature and salinity from an ice-tethered profile (ITP-74) off Siberia in July 2014. Note the warm Atlantic water below 150 meter depth.

A single profile of temperature and salinity from an ice-tethered profile (ITP-74) off Siberia in July 2014. Note the warm Atlantic water below 150 meter depth.

Some wonderful and new science and engineering gives us a new instant perspective on how temperature and salinity change over the top 700 meters of the Arctic Ocean every 6 hours. Scientists and engineers at the Woods Hole Oceanographic Institution with much support from American tax-payers keep up many buoys that float with the ice, measure the oceans below, and send data back via satellites overhead to be posted for all to see on the internet. Over the last 10 years these buoys provide in stunning detail how the Arctic Ocean has changed at some locations and has been the same at other locations. I used these data in an experimental class for both undergraduate and graduate students to supplement often dry lecture material with more lively and noisy workshops where both I and the students learn in new ways as the data are new … every day.

For well over 50 years the Soviet Union maintained stations on drifting Arctic sea ice that stopped when its empire fell apart in 1991. Russia restarted this program in 2003, but unlike the US-funded automated buoys, the Russian-funded manned stations do not share their data openly. No climate change here …

Shellshock Bugs, Macs, and Unix Powers

I love my Apple to bits. My writing, teaching, coding, graphing, and playing are all done on a MacBookPro with two Intel 2.4 GHz processors running OS X 10.5.8 called “Leopard.” It was the up-to-date operating system from 2006-2009 and I never saw the need to change, as I was too lazy to fix something that is not broken. Until today when I learnt of a vulnerability deep inside the guts of my beloved Unix-machines.

For over 5 years this laptop has been running non-stop doing scientific computing on huge amounts of ice, ocean, and satellite data. It is this Unix environment that I cherish as it is open, transparent, elegant, and concise. It also allows me to use unlimited codes and tools of many open-source communities. My Apple also traveled with me on ships and planes to Arctic Canada, Greenland, Norway, Germany, and anywhere in-between. It travels daily on my bicycle from home to work and back.

Today I was worried when my student Pat told me about shellshock, a bug that potentially can give control to a hostile party smart enough to exploit this vulnerability for which Apple has not yet released a patch. So, did I have a problem? You bet.

STEP-0: From a terminal I entered the command

env x='( ) { : ; }; echo vulnerable’ bash -c “echo this is a test”

If the word “vulnerable” appears, then the bug is present. Also check the second flavor of the bug by entering the command

env X='( ){(a) =>;\’ bash -c “echo date”; cat echo; rm -f echo

If you see the actual date displayed (as opposed to the word “date”), then again you got the buggy code. Here is how I fixed it on my laptop and MacMini that hosts my work web-pages.

Step-1: I took this technical recipe, but not all elements worked for me:

$ mkdir bash-fix
$ cd bash-fix
$ curl https://opensource.apple.com/tarballs/bash/bash-92.tar.gz | tar zxf –

The above line failed me, but the added option -k worked to download the needed files from apple.com with the curl-command; the same was also true for the two other curl commands below that downloaded the patches from gnu.org It applies the patches to the files uploaded from apple.com prior.

$ curl -k https://opensource.apple.com/tarballs/bash/bash-92.tar.gz | tar zxf –
$ cd bash-92/bash-3.2
$ curl -k https://ftp.gnu.org/pub/gnu/bash/bash-3.2-patches/bash32-052 | patch -p0
$ curl -k https://ftp.gnu.org/pub/gnu/bash/bash-3.2-patches/bash32-053 | patch -p0
$ cd ..
$ sudo xcodebuild

STEP-2: The above line “sudo xcodebuild” did not work for me for reasons I do not understand. I realized, however, that it was supposed to compile the patched codes to produce executable new files “bash” and “sh” free of the bug. I searched for and found the code-building application XCode.app on my computer as /Developer/Application/XCode.app and started it by point and click. Then via File > Open File I found the relevant “project file” bash.xcodeproj that was in the directory created previously, that is, bash-fix/bash-92 which I then opened within XCode.app Hit the button with the hammer called “Build and Go” and you build yourself a new bash.

Screenshot of compiling patched bash.xcodeprof using XCode.app

Screenshot of compiling patched bash.xcodeprof using XCode.app

STEP-3: Once the compilation and building of the executables is complete, all that needed to be done was to move the newly created, patched executable shells “bash” and “sh” into their rightful places deep within the guts of the operating systems. First, however, lets just save the buggy old files. From the command line

$ sudo cp /bin/bash /bin/bash.old
$ sudo cp /bin/sh /bin/sh.old

and as the last step move the new, patched “bash” and “sh” to their
root directory /bin:

$ sudo cp build/Release/bash /bin/.
$ sudo cp build/Release/sh /bin/.

I moved the binary files “bash” and “sh” to my web-hosting MacMini after renaming the old buggy ones, oh, and as a good practice (short
of deleting those old system files), I changed the permission settings.

Credit for this way to reduce a vulnerability on my dear machine belongs to this concise blog whose content is also presented in a more chatty voice. Wired Magazine adds a little drama in their story titled “The Internet Braces for the Crazy Shellshock Worm, but it took me longer to write and assemble this essay than it did patching the bug.

Unix is fun to hack.
Eric S. Raymond

Unix is not so much an operating system as an oral history.
— Neal Stephenson

ADDENDUM Sept.-28, 2014: A quick online to test for vulnerable web-sites and cgi scripts.

ADDENDUM Jan.-6, 2015: I apparently missed 3 more vulnerabilities that the above test may not check for, e.g., http://tenfourfox.blogspot.com/2014/09/bashing-bash-one-more-time-updated.html

A Short Summary of Nares Strait Physics

The Arctic Ocean is a puddle of water covered by ice that melts, moves, and freezes. Grand and majestic rivers of Siberia and America discharge into the puddle and make it fresher than Atlantic Ocean waters. The fate of the Arctic freshwater helps decide if Europe and the US become warmer or colder, experience more or less storms, droughts, or floods, and if global sea level will rise or fall. In a nutshell: the fate of Arctic freshwater determines climate.

Arctic Ocean with Nares Strait study area (red box) with tide gauge locations as blue symbols and section of moored array as red symbol. Contours are bottom topography that emphasize ocean basins and continental shelf areas.

Arctic Ocean with Nares Strait study area (red box) with tide gauge locations as blue symbols and section of moored array as red symbol. Contours are bottom topography that emphasize ocean basins and continental shelf areas.

Nares Strait connects the Arctic and Atlantic Oceans to the west of Greenland. It is narrower than Fram Strait, but it transports as much fresh ocean water as does its wider sister facing Europe. Few people know this, including climate scientists who often model it with a bathymetry that is 10,000 years out of date from a time when Nares Strait did not yet exist. This is why the US National Science Foundation funded a group of oceanographers to use icebreakers, sensors, computers, and innovative engineering to collect and analyze data on the ice, the water, and the atmosphere.

Acoustic Doppler Current Profiler mooring deployment in Nares Strait from aboard the CCGS Henry Larsen in 2009.

Acoustic Doppler Current Profiler mooring deployment in Nares Strait from aboard the CCGS Henry Larsen in 2009.

Within days of the start of the grant I had to appear before the US Congress to answer questions on Petermann Glacier that discharges into Nares Strait. In 2010 a large 4-times Manhattan-sized ice islands broke off and people wanted to know if global warming was to blame. I was asked how ocean temperatures and currents relate to this and other events and what may happen next. My few data points were the only existing data for this remote region, but I had not yet had the time to analyze and publish much. Two years later another large 2-Manhattan sized ice island formed from the same glacier, but this time we were better prepared and people world-wide went directly to our data, thoughts, and stories when this blog was sourced in news papers in France, Germany, and China. Al Jezeraa, BBC, and PBS reported on it, too, giving me chance to connect via TV, radio, and pod-casting to a larger public.

Petermann Gletscher in 2003, 2010, and 2012 from MODIS Terra in rotated co-ordinate system with repeat NASA aircraft overflight tracks flown in 2002, 2003, 2007, and 2010. Thick black line across the glacier near y = -20 km is the grounding line location from Rignot and Steffen (2008).

Petermann Gletscher in 2003, 2010, and 2012 from MODIS Terra in rotated co-ordinate system with repeat NASA aircraft overflight tracks flown in 2002, 2003, 2007, and 2010. Thick black line across the glacier near y = -20 km is the grounding line location from Rignot and Steffen (2008).

While it was exciting and fun to share Nares Strait and Petermann Gletscher physics with a global audience, it is not what we had planned to do. Our goal was to put real numbers to how much water, ice, and freshwater was moving from the Arctic to the Atlantic via Nares Strait. So the next 3 years we labored through our extensive records to first describe and then to understand what was happening in Nares Strait. We found that ocean currents move water always to the south no matter if ice covers Nares Strait or not, no matter if the ice is moving or not, no matter which way the wind is blowing. The physical cause for this southward flow is that the sea level is always a few inches higher in the Arctic Ocean than it is in Baffin Bay and the Atlantic Ocean to the south.

Linear regression of volume flux  through Nares Strait from current meters with along-strait sea level difference from tide gauges (unpublished).

Linear regression of volume flux through Nares Strait from current meters with along-strait sea level difference from tide gauges. (unpublished).

We know, because we measured this with tide gauges that we placed in protected coastal bays. We recovered 3 sensors; most rewarding was the recovery of one sensor that we had failed to reach in 2005, 2006, 2007, and 2009, but in 2012 we finally got the instrument and 9-years of very good data. Batteries and computers inside were still running and recording. I have never seen as clean and as long a time series.

Results from a 2003-12 tide record shows as power spectra with named tidal constituents at diurnal (~24 hours) and semi-diurnal (~12 hours) periods. The red line is a modeled red noise spectra (unpublished).

Results from a 2003-12 tide record shown as a power spectra with named tidal constituents at diurnal (~24 hours) and semi-diurnal (~12 hours) periods. Data are shown as the relative amplitudes of oscillations at frequencies in cycles per day or cpd. The red line is a modeled red noise spectra (unpublished).

From satellite data that we analyzed as part of this grant, we know when the ice moves and when it stops moving. The freeze-up of Nares Strait comes in one of three forms: 1. Ice stops moving in winter, because an ice barrier (ice arch or ice bridge) forms in the south that blocks all southward motion of ice; 2. only new and young ice moves southward, because an ice barrier forms in the north that blocks all entry of Arctic ice into Nares Strait; and 3. Arctic ice moves freely through Nares Strait, because no ice barriers are present. Our 2003-12 study period covers years for each of these different ice regimes. And each of these regimes leads to very different ocean (and ice) flux as a result of very different ocean physics.

Data alone cannot make definite statements on what will happen next with our climate, but we know much new physics. The physics suggest certain balances of forces and energy for which we have mathematical equations, but these equations must be solved on computers that can only approximate the true physics and mathematics. These computer models are our only way to make predictions ito the future. The data we here collected and our analyses provide useful checks on existing models and will guide improved models.

June-10, 2012 MODIS-Terra image showing location of moored array that was deployed in Aug. 2009 to be recovered in Aug. 2012.

June-10, 2012 MODIS-Terra image showing location of moored array that was deployed in Aug. 2009.

Johnson, H., Münchow, A., Falkner, K., & Melling, H. (2011). Ocean circulation and properties in Petermann Fjord, Greenland Journal of Geophysical Research, 116 (C1) DOI: 10.1029/2010JC006519

Münchow, A., Falkner, K., Melling, H., Rabe, B., & Johnson, H. (2011). Ocean Warming of Nares Strait Bottom Waters off Northwest Greenland, 2003–2009 Oceanography, 24 (3), 114-123 DOI: 10.5670/oceanog.2011.62

Münchow, A., Padman, L., & Fricker, H. (2014). Interannual changes of the floating ice shelf of Petermann Gletscher, North Greenland, from 2000 to 2012 Journal of Glaciology, 60 (221), 489-499 DOI: 10.3189/2014JoG13J135

Münchow, A., Falkner, K., & Melling, H. (2014). Baffin Island and West Greenland Current Systems in northern Baffin Bay Progress in Oceanography DOI: 10.1016/j.pocean.2014.04.001

Rabe, B., Johnson, H., Münchow, A., & Melling, H. (2012). Geostrophic ocean currents and freshwater fluxes across the Canadian polar shelf via Nares Strait Journal of Marine Research, 70 (4), 603-640 DOI: 10.1357/002224012805262725