The end is nigh

Harken, brethren and sisters, it is soon that VERDI hath passed its last of days! Behold this heavenly sign, unmistakably foreboding the final hour! The Sun itself, our celestial guide, hath covered its radiance with a selenic veil.

The safe way to observe this partial solar
eclipse: project the solar disk through
a detached photo camera lens.

Without exposing the eye, a camera
can take a decent photo with the
shortest exposure, the smallest
aperture, and sunglasses.

Today's solar eclipse was annular (ringförmig) in the central Pacific Ocean and the western USA. In Inuvik, it was still a partial eclipse (50%).

We prepare to leave

On Friday all of the equipment that goes to Muskoka with the Polar 5 was packed into the aircraft. Saturday morning the aircraft left for Muskoka (with an overnight stop planned for Winnipeg). Sunday most of the science team left as well, partly for Muskoka, partly home to Germany. Only Eike and myself stay until Monday, then we leave as well for Muskoka.

Calibrating: Drive in circles

This rather cryptic message from our rental car left us somewhat confused!

Last Science Flight!

A hyperspectral image of Inuvik Airport,
converted to true colours.

On 17 May 2012, we performed the last VERDI research flight. We probed the same cloud area as on the previous days. Again, there were some ice crystals in the cloud although the temperature was pretty warm, between -4°C and +4°C throughout the cloud. We followed a pair of parallel tracks above and through the cloud layer, and in the end we flew two butterfly patterns for the geometrical calibration of the hyperspectral camera, Eagle. For that we need to look at a distinct surface pattern at different angles.

With this flight, we have used up all our flight hours. Thanks to Alfred Wegener Institute for providing the aircraft and the generous flight hours, and to Aurora Research Institute for the excellent support in Inuvik!

Flight May 16

Inuvik from above

Another flight into the same area. Having snow showers (flurrys as the showers with low intensity are called here) at the airport we were sure that these clouds have to contain ice. In the target area this time we continued heading west expecting a change in the cloud properties indicated by a second cloud field in the satellite images and almost reached US airspace. The cloud field in the west we just missed. But indeed the clouds did change. Cloud top decreased and thickness as well. On the way back we first did not found many ice particles. Later further east the number of ice crystals increased more and more. On our way back to Inuvik we stayed below cloud bottom and collected some more precipitating ice crystals and images of Inuvik and the Mackenzie Delta,

It's winter again

Surprisingly it did start snowing again during this night. Remember the T-shirt weather two days ago!!! Similar to yesterday northerly winds blow cold air into the Mackenzie delta and generate clouds and even precipitation. We expect to have another flight into the same area sampled yesterday. Hopefully it will also snow there.

(Some) ice is back: Flight on 15 May

Turning back to go through this nice
Cumulus cloud once more.

Today we flew into the same area as yesterday. The cloud was still there, and it was in fact a little different than the first time. We even saw ice crystals in the cloud! We probed it on a east-western and a north-southern leg, and found differences between all the waypoints. The "icing on the cake" of this flight was a cumulus cloud on the way home. There were no convective clouds in this area before yesterday, so this something new for VERDI, and of course we did a few turns inside it. The cumulus contained aggregate ice particles, and finally the flights became a little bumpy.

The Niagara Falls of Inuvik

The high temperatures of the last days lead to heavy melting and a lot of runlets bringing water from all over the town to the Mackenzie.

Today a strong and cold wind from the north produced fog in our area with temperatures again below zero.This delays the flight planned for today. Hopefully we get into the air around noon heading for the same area and clouds as sampled yesterday.

Flight into clouds, 14 May

Canada Is the country of lakes. There is no
official estimate of the total number of
lakes in Canada; three millions is a first
inofficial guess. Start counting here: The
Mackenzie delta is nothing but river arms and
lakes between small dry stretches with trees.
The contrast between dark trees and white
ice makes the counting easier in winter!

Finally, after a couple of days of sunshine and leisure, the clouds came back. Inuvik itself is still sunny, but a low cloud deck has formed over the southern Beaufort Sea. And it seems it's there to stay, so probably today's flight is the first of a series. We targeted two cloud areas. The first ended earlier than expected, and the second had a double cloud layer. We probed the cloud at several altitudes in both layers, and inbetween. Alas, it is too warm to find ice particles in the cloud! Nevertheless, clouds over the sea ice are always of interest. And these ones were different from the ones on all the previous flights, so we are quite happy.

Current weather forcast

Although everybody of the locals might be happy with such a forecast for our reasearch flights this picture is a bit frustrating. Fortunately the ECMWF forcast differs and predicts clouds above the Beaufort sea for late Monday and Tuesday.

Wildlife

On  a day without flying, we have time to explore the surroundings of Inuvik. Even up here, there is considerable wildlife. There are also moose, but all we saw of that was brought to us in a pot, hot and very tasty, by local hunter and guide Donald.

The local variety of the arctic hare

Female grouse/ptarmigan, in transition to summer plumage

Bald Eagle

Road Closed

Today we made a day off (with very nice weather) and six of us took the Dempster-Highway southbound. About 110 km south of Inuvik the "Highway" crosses the frozen river.

But the ice river crossing was already closed because of the warm temperatures. And for good reaosn, as I found out when I sank through the snow and found out that there is indeed liquid (but ice cold) water underneath. My tennis shoes and socks were soaked!

Inuvik vs. Leipzig

After flight on May 10th the big melting started

Thursday was temporalily the last flight for the next days. Since yesterday spring has started in Inuvik. Everything melts, ponds an small lakes are filling up, cars and other things appear again below the melting snow. Unfortunately the temperatures are above zero as well in the altitude levels of potential clouds. This means, there is defenitely no ice in this clouds. That's why we decided to have a break and wait for colder temperatures before having further flights. From Monday conditions are predicted to improve. Until then we hope to reassamble all instruments on board of Polar 5. The repaired 115V-inverters will be installed again and hopefully the CAS-DPOL will arrive everyday that we can start the last week of measurements with full strength.   

A short recapture of Thursdays flight. Again we probed low level clouds above the beaufort sea. Close to the coast we also observed a second higher cloud layer which we intended to probe on our way back. Unfortunately these clouds almost have cleared away when we arrived. Only a small fraction could be probed. The low level showed up to be thicker than the days before. The icing was heavier forcing us to leave cloud top before the probing was complete. After letting the ice melt in the sun the last remaining probing level could be repeated. 

Home cooking

In preparation for the incredibly expensive food (e.g., 1l milk=3 $), one box of basic food supply was send to Inuvik. Most of us are cooking now in the kitchens of our row houses. Only pasta seems not to be welcome anymore. Or someone just miscalculated the demand on noodles. These are 2kg packs!

With everyone being filled up the next flight is planned for tomorrow before the temperatures increase above freezing point. Unfortunately this is unfavorable for the ice crystals we are looking for.

Flight on May 8

This was my first research flight on the Polar 5. We thought we had the ALABAMA mass spectrometer repaired, but in flight some new problems came up, so I had a lot do to with the instrument. In the end I did not record more then 3 (!) mass spectra, which is close to nothing. However, we think that we fixed some problems after the flight and on the next day, so there is still hope. As far as I heard, all the other instruments worked well.

De-icing required

The snowfall during the night and temperatures around zero show up to be a bigger problem for todays flight than expected. Polar 5 was covered with a thin ice film which made a de-icing of the entire wings neccessary. This delayed the planed take off about 1 1/2 hours. Fortunately the cloud situation did not change dramatically during this time, as seen from the ground. Now we have to wait what the crew will report after coming back from the flight.

No flight today, but lots of snow

The cloud situation was not very promising today. So we decided to spend another day to work on some instrument issues and wait for long-awaited spare parts. The local weather was not good either. Snow during the whole day. Everybody was reminded of christmas time. Even the Dempster highway was covered by snow again. In the forest close to the Dempster we could find a lot of large Bigfoot traces. Maybe worth to be published in Nature or Science.  

Row Houses

This is where most of us are staying: Friendly small row houses, each with three bedrooms, a living room and a kitchen. Eating out is quite expensive here, so the opportunity to cook for ourselves is highly appreciated.

Ice Road

Although today we had maximum temperatures of about -10°C, the ice road season has been officially closed now. Obviously for the good reasons as some local did learn today. However, on foot it is still traversable. At some places you can see how thick the ice is. Looks like more than one meter.

Flight on 3rd of May

Thin clouds that are barely visible
on the satellite image (NASA
MODIS-Terra, 3 May 2012)

On the third day of May, our flight brought us to a very low and shallow cloud deck over the sea ice of the Beaufort Sea. We had taken the coordinates for our flight destination from cloud forecasts and satellite images, but by the time we arrived at the location where the cloud should have been, all we saw was the sea ice and a blue sky. So we kept going north (whither the cloud was withdrawing), and soon we could see first patches of clouds. We cannot go into a cloud when it is very low, because the aircraft needs a safe distance from the ground. But with AMALi, our lidar instrument, we knew that the cloud was in fact just high enough to go in. So we scanned the cloud from above for a while, and then went down and flew through the cloud on the same way back.

Our team

Photo by Ralf Weigel

We are having a little break due to an unattractive cloud situation. We use the time to look at the data collected so far, to give the aircraft due maintenance, and to take this picture of our team in front of the Polar 5 at Inuvik Airport. Greetings to the folks at home who enjoy 20°C — look at the snow in the background and our hats. Temperatures here will stay below freezing for the next days.

Ice clouds and snow

A 22° halo brightened by a lower
tangent arc indicates columnar
ice crystals

On 30 April, we flew through a more complex cloud pattern, with a patchy layer of an ice cloud at around 3 km altitude, and a low mixed-phase cloud near the surface. A snowing cloud was probed at various levels, and should provide a good challenge to test precipitation models.

The perfect low cloud

The ideal model cloud

On the flight on 29 April, we found the ideal textbook cloud: an extensive low-level mixed-phase cloud with clear sky above it. This is what one-dimensional radiative transfer models have been written for! In this cloud, we found liquid droplets that were 20 micrometers large on the top and 10 micrometers at the bottom. Toward the bottom, ice crystals were also found in this cloud.

Double Flight

On 27 April, we performed two flights in a row. The flight track was the same for both flights. A few mid-level and a closed deck of low-level clouds was observed on the first flight. On the second flight in the afternoon, both layers were already dissolving. It will be interesting to compare these two development stages in the data.

A closed layer of low clouds before noon

The same layer dissolving in the afternoon,
revealing the sea ice under it

Weather Forecast for Inuvik from Leipzig students

Weather Forecast for Inuvik, Canada

Date: Friday, April 27th, 2012

General Weather Situation:
A low pressure system over the Gulf of Alaska moves toward the northeast and weakened further to the west coast from Canada. At the same time a high wedge is over the North American continent to the Arctic Ocean. To the northwest of Inuvik, a low pressure area is generated, which will deepen in the course of the weekend.

Further course of the day:
After a foggy night, the gloomy weather will hold during the day. Out of the fog, it can snow in the late afternoon light scattered. The temperatures after a cold night at -12 ° C increases day by up to values ​​of -4 ° C. The wind is blowing from the northwest while weak.

Weekend weather:
At the weekend the aging low draws from the Pacific coast across northwestern Canada. Furthermore, it will unite with the generated low over the Beaufort Sea.
After foggy early Saturday, there will also later in the day be no change in the weather, leaving it dry. It was not until Sunday afternoon, the sun is expected to show again. Temperatures range from -12 ° C at night to about -3 ° C during the day. The cyclonic wind shifts on the weekend from northwest to east.

Further outlook:
After the meantime weak gradient, there will be a new low pressure area north of Alaska closer to the continent, which will lead to renewed motion for Inuvik weather.

© LIM, erstellt von Martin Schmidt

This was the last weather forecast from Leipzig students.
Have a good time!

The end of the line

When a supply helicopter dropped its goods right onto the one glass fiber that connects Inuvik to the outer world, we had the chance to experience life without internet and telephone for a day. Right now, it is all back working. Today's flight, however, was cancelled due to low clouds and poor visibility at Inuvik airport.

Weather Forecast for Inuvik from Leipzig students

Weather Forecast for Inuvik, Canada

Date: Thursday, April 26th, 2012

General Weather Situation:
Inuvik is still under the influence of an upper-level ridge which moves eastbound and hence clears the way for a newly established upper-level trough above the Arctic Ocean. To the west there is an ageing low pressure system in high air layers. On the ground high air pressure with a low pressure gradient is persistent.

Course of the Day:
Thursday is characterized by medium cloud coverage. Towards the evening it will be clear. Flurries in the morning and afternoon cannot be excluded. Light winds blow steadily from the northwest. The temperature will vary between -10 and -4°C (14 to 28°F).

Forecast for Friday, April 27th, 2012:
Friday will start with a cold temperature of -15°C (5°F). Throughout the day the values will not exceed -5°C(23°F). In the morning fog depositing rime is possible and will probably not thin out so that there will be clouds all day long. But sunny intervals can occur, too. There won't be any snow on Friday. The wind remains unchanged in direction and force.

Forecast for Saturday, April 28th, 2012:
At the beginning of the day there will be a temperature of -12°C (10°F) and an overcast sky. Towards the evening it will become sunny so that as a result we will reach -4°C (25°F) in the afternoon. There will still be light winds blowing from northwesterly directions. Flurries are possible during the course of the day.

Further Outlook:
The newly formed upper-level trough above the Arctic Ocean will intesify but won't have an impact on the weather in Inuvik just yet. On the ground the polar cold high remains and leads to sunny following days. Because of the weak pressure gradient the wind will continue to blow lightly.

© LIM 2012, Sarah Grawe

Weather Forecast for Inuvik from Leipzig students

Weather Forecast for Inuvik, Canada

Date: Wednesday, April 25th, 2012

General Weather Situation:
Northern Canada is under the influence of an upper-level ridge which borders on an ageing low pressure system in the west above the Gulf of Alaska. The cold high on the ground and the high pressure in upper air layers are decisive for Inuvik.

Course of the Day:
After a cold night with a temperature of -15°C (5°F) the day will be consistently sunny with values around -3°C (27°F). In the evening it will cool down quickly due to nonexistent cloud coverage. It will remain dry. Light winds will blow from easterly directions throughout the day.

Forecast for Thursday, April 26th, 2012:
Towards Thursday the upper-level ridge will shift eastbound and an upper-level trough will develop above the Arctic Ocean. On the ground, though, high pressure will persist. After -15°C (5°F) at sunrise the day will beginn clearly and the sky will continue to be free of clouds in the following. The temperature will reach -5°C (23°F) and there won't be any precipitation. The wind will blow lightly and change its direction to northwest during the night.

Forecast for Friday, April 27th, 2012:
In the early hours on Friday fog depositing rime is possible and may not thin out throughout the day. For that reason the temperature will only vary within a small range between -9°C (16°F) and -6°C (21°F). Light snow showers may occur during the day. There will be a soft breeze from northwesterly directions. 

Further Outlook:
The next few days will be characterized by the influence of high air pressure which will be replaced by a low pressure system moving in from Alaska towards the end of the weekend. Because of a weak pressure gradient eventual fog may occur together with snow showers at daytime.

© LIM 2012, Martin Schmidt

One kind of bear is everywhere

Who ever said that licence plates have to be rectangular?

Third flight, 23 April

A pingo in the snow.

We headed out north-west for another sea-ice study. Unfortunately, continuous low clouds made it impossible to deploy the EM Bird this time. Instead, we probed a haze layer which the mass spectrometer detected at around 2400 m altitude. On the way back, we could see a few pingos near Tuktoyaktuk, hills created by the permafrost.

Second flight, 22 April

The EM Bird is installed under
the aircraft belly.

Thin ice on a re-frozen open lead in the ice.

The ice looks fascinating from
this close perspective.

The EM Bird is monitored by a video camera.
Here you can see it in the top center.

A successful flight for the sea-ice studies was conducted today over the Beaufort Sea. The EM Bird is an electromagnetic sonde that uses the conductivity of sea water to detect the bottom of the sea ice. The top of the ice is observed with a lidar altimeter, and the difference is the sea-ice thickness. For these surveys, the aircraft flies 65 meters above the ice, at 55 m/s, and the Bird is towed on a 200-ft rope so it is near the ice.

Weather Forecast for Inuvik from Leipzig students

Weather Forecast for Inuvik, Canada

Date: Tuesday, April 24th, 2012

General Weather Situation:
Northern Canada is still under the influence of a low pressure system above the Aleutes which is moving westwards and will combine with another low to the south of Alaska. Furthermore the polar high continues to be located in the Arctic region and has an effect on the weather in Inuvik even if there is barely any movement of air masses noticeable.

Course of the Day:
In the morning there is a chance of fog which will thin out until noon. Afterwards it will be sunny but from time to time medium high cloud banks will move across the sky. It will remain dry. After a cold morning with a temperature of -11°C (12°F) we will reach values of just above freezing. In the evening it will cool down quickly due to little cloud coverage. The wind blows lightly from easterly directions throughout the day.

Forecast for Wednesday, April 25th, 2012:
Initiated by subsiding air masses, clouds will dissolve and the morning will beginn clearly with a temperature of -9°C (16°F). During the day it will remain sunny. The maximum temperature will not exceed the freezing point. Precipitation is not to be expected. There will be light winds from easterly and in the evening from southeasterly directions.

Forecast for Thursday, April 26th, 2012:
In the course of the night the sky will become increasingly overcast. As a result isolated snow showers are possible in the morning and also during the day. The temperature varies between cool -7°C (19°F) at sunrise and not more than -2°C (28°F) at daytime. Starting from the early hours light winds will blow from northerly directions.

Further Outlook:
Towards the weekend the low to the south of Alaska will dissolve. Simultaneously a new low above Northern Canada will establish and intensify. This may lead to further snowfall.

© LIM 2012, Martin Schmidt

We would be very pleased if any of you could send me pictures of the sky of a few times the day. We need this for our seminar because there is no webcam for Inuvik. Thanks a lot!

Weather Forecast for Inuvik from Leipzig students

Weather Forecast for Inuvik, Canada

Date: Monday, April 23rd, 2012

General Weather Situation:
At the moment Northern Canada is influenced by the Aleutian Low to the west of Alaska as well as a thermal high situated in polar regions. An upper level ridge to the east of the Aleutian Low extends to the Northern Territories. However, Inuvik is located in an area affected by a low pressure gradient. As a result there is no distinct weather activity.

Course of the Day:
After a cold night with a minimum temperature of -10°C there will be an increase until just below freezing point which will be reached in the afternoon. Light winds blow from easterly and northeasterly directions. For the greater part the sky will be overcast with sunny intervals around noon. In the evening it will be clear. There won't be any precipitation during the day.

Forecast for Tuesday, April 24th, 2012:
The low pressure system above the Aleutes has moved to the southeast and is now located to the south of Alaska. Therefore Inuvik is influenced by an air flow from southerly directions. In the early hours the minimum temperature will reach -7°C, in the afternoon values above 0°C are possible. There will be a continously gentle breeze from easterly and southerly directions. After an overcast morning it will be sunny with cloudy intervals. It will remain dry again.

Forecast for Wednesday, April 25th, 2015:
During the night the temperature will sink to -7°C and approach 0°C during the day. Light snowfall and a full cloud coverage are likely. The wind will blow gently from easterly directions.

Further Outlook:
Within the next few days the low pressure system to the south of Alaska will shift further south. The development of a new low above Alaska will lead to changing weather.

© LIM 2012, Martin Schmidt
uploaded by mobile

Flight #1

Flight track in Google Earth with
today's NASA MODIS satellite overlay

A large open lead in the Beaufort Sea

Today at 10:24 (Mountain Daylight Savings Time), that is 1624 UTC, the Polar 5 took off for the first VERDI flight in Inuvik. It was a Bird mission, so we headed onto the sea ice, expecting cloud-free conditions in the target area. But there were low, foggy clouds that were missed on the satellite pictures, so conditions were not good: the clouds decrease the pilots' visibility, and the humidity seemed to irritate the Bird. On the way back, the remote-sensing equipment scanned the low clouds and the sea ice, which has several large open leads, also an interesting topic. The flight ended at 13:53 in Inuvik.

No flight today

Due to low cloud cover here and over the ice on the Beaufort Sea, our first science flight will not be today. The first few flights will be with the towed EM Bird, which is lowered down to a few meters above the sea ice. That is a tricky manoevre for the pilots, and they need good visibility. Low clouds are a dealbreaker for that kind of mission. Instead, we work on a few more technical issues of our instrumentation.

Arrived

Both the Polar 5 aircraft and the crew have arrived in Inuvik. As you can see in the pictures, we have snow again! From Yellowknife to Inuvik you fly along the Mackenzie River, which is still ice-covered, just like the thousands of lake that speckle the Canadian landscape. We have settled in the Aurora Research Institute's dwellings, and their office buidling is very nice and modern with a well-equipped conference room. Their staff is really nice and very helpful. The main road is ice-free, and we start to find our way around town.

Across Canada

The Polar-5 has left Muskoka in the morning of 18 April, with lots of cargo. It will take them three stops before they get to Inuvik, while the science crew is taking commercial flights via Edmonton.

Take off for test flight

At April 17 the Polar5 took off at 14:00 local time from Muskoka Airport for the test flight.

Test Flight

Today (17 April) we accomplished a two-hour test flight starting and landing at Muskoka Airport. Take-off was delayed by snowfall, but by the end of the flight the sky was clear. The instrumentation of the 'Sea-ice' configuration was installed on the aircraft and put to a test in airborne action. The flight was also used for certain calibration procedures. You can see how many circles there were in the flight track, including two at a bank angle of 45°. Funny enough, after completion of such a circle the aircraft encounters its own wake, which could be felt distinctively. The atmosphere was pretty bumpy to begin with, so it was a pleasant ride for those who love rollercoasters. The views of the Lake Huron and of Muskoka's forests and lakes were magnificent. Unfortunately, the test flight also revealed a few faults that need to be fixed.