Kilimanjaro Climate & Glaciers

January ablation

2012-02-08T13:39:00.001-05:00

The 2011 short rains on Kilimanjaro summit continued untilthe very end of December, with most snowfall occurring during the second halfof November. For the season, net snow accumulation on the Northern Ice Field amountedto ~30 cm.

The image above shows an easterly view across the crater on 28December, just prior to the year’s final snowfall event; snowcover in thecrater is often “patchier” than that on the glaciers (credit: Rohun Gholkar). On the graph, the timing ofthis photograph is indicated by the light blue star. After departing thesummit, Rohun’s team encountered sleet and rain, which was likely associatedwith 3 days and ~10 cm of snowfall on the glacier (see graph; dashed lineindicates midnight on New Year’s Eve).

Very little snowfall occurred during January 2012, as shownin the lower figure, resulting in a net surface height lowering of 19 cm. Two 48-hour intervals of rapid lowering are highlighted byred lines on the graph. Based on weather station measurements received by satellitetelemetry, these seem to have been intervals of enhanced sublimation. We cannotbe certain, but this interpretation is based on the following, which pertainsto both intervals: air temperature was2.0 – 2.5° C lower than normal for January, the sky remained mostly clear, windspeed was ~50% higher than normal (directly from the east), and relativehumidity averaged a very low 20-25% instead of ~60% as on a typical Januaryday. Together, these are perfect conditions for sublimation.

Any first-hand observations and/or photos from the summit areaduring these dry intervals (Jan. 1 & 2, Jan. 22 & 23) would be greatlyappreciated!

Heavy rainfall in Dar es Salaam

2011-12-22T12:14:00.001-05:00

Dar es Salaam experienced extremely heavy rainfall yesterday, with one source reporting a 24-hour total at the airport of 233 mm. An article in The Muslim News quotes a Tanzania Meteorological Agency (TMA) source reporting 156.4 mm. Either one is apparently the highest 24-hour amount since the mid 1950s.

Flooding and lightning strikes have killed at least 20 people according to the BBC, and left thousands homeless. The event has reportedly crippled the city of Dar, destroying considerable infrastructure. TMA forecasts the heavy rains to continue over the region.

Snowfall data and accounts from Kilimanjaro are not available yet. Being convective in nature, the heavy rainfall may not be widespread.

[UPDATE 12/30 & 1/3/12: Snowfall began at the station on Wed., 28 Dec. and continued to the 31st. Telemetry indicates ~11cm of accumulation for the event, which is certainly a significant snowfall by Kilimanjaro standards. Tim from SENE was recently on the mountain, so perhaps we'll have a first-hand report soon.]

East African Drought

2011-12-20T15:12:00.001-05:00

The Weather Underground blog has a helpful discussion of the drought which so terribly impacted East Africa this year, and author Jeff Masters points out that it was 2011's deadliest weather disaster. He annotates several figures from NOAA's Climate Prediction Center (above), showing that the drought was concentrated to the north of Kilimanjaro. Likewise, the most anomalous rainfall through the currently-underway short rains season has also been further north. On the mountain, the relative snowfall amounts are consistent with regional patterns depicted in the figures.

Masters also provides some thoughts on East Africa's future vulnerability. Considerable uncertainty exists between measured precipitation trends, and that predicted by models due to changes in Walker circulation. Kilimanjaro snowfall and glacier mass balance measurements support evidence from station data for steady drying of the climate in recent decades.

Fieldwork photos

2011-12-20T09:21:00.001-05:00

Finally... images from September-October fieldwork have been processed, and a selection is now posted here! This trip was especially enjoyable and productive, as hopefully conveyed by the photos.

More ice sampling

2011-10-19T14:35:00.000-04:00

In 2009 we collaborated with researchers at Paul Scherrer Institute (Switzerland) to test new techniques for dating glacier ice (more here). Encouraging results justified further investigation, which was part of our recent fieldwork. Here is a short clip illustrating this year's approach to sampling; note that September weather wasn't quite as dry as normal!

Early Short Rains?

2011-10-19T14:30:00.000-04:00

A recent posting here discussed a multi-day August snowfall event which resulted in ~5cm of accumulation on the Northern Ice Field. The next month or so was relatively dry, as typically the case at this time of year, with only about 14cm of ablation due to relatively high albedo following the mid-August snowfall event.

At the Northern Ice Field AWS, the next snowfall event appears to have occurred on 20 September, the day our team arrived in Tanzania. More snowfall was recorded on the 23rd, when we waited - in the rain - for our final permits at park headquarters in Marangu. Ascending the mountain we encountered light precipitation on a few days. However, while setting up camp in the crater on the 29th, a snow squall brought another 3-4cm of accumulation to the glacier.

The next snowfall occurred during the night of October 1st, apparently associated with tremendous convection visible to the East and accompanied by lightning and thunder, the most we have ever seen from the summit. By morning, camp was blanketed by a uniform 6cm of new snow, with more variable accumulation on the glacier. Rather fortuitously, the AWS had been reset into the ice the previous day; disturbance of the glacier surface is unavoidable during this process. Perfect timing for a snowfall event!

Telemetry from the AWS indicates continuing accumulation since we departed on the 4th, with snowfall on the 5th and a multiday event from ~11-15 October. With net accumulation of ~5cm to mid-October, little additional ablation is likely in the next few months - especially if the Short Rains have indeed begun.

Finally, anecdotal reports from around the mountain support the idea of an early Short Rain season. For example, a note from 17 October indicated "lots of rain on Kilimanjaro" which made climbing very difficult for some clients (Ngorogoro Camp and Lodge). Also from the 17th, several reports of rain "every day" in Arusha. In the week prior, perhaps coinciding with the multiday event on Kilimanjaro, a storm over Kibwezi, Kenya (just north of Kilimanjaro) "was so intense that it prevented small aircraft from going to the coast."

Fieldwork!

2011-10-11T14:26:00.001-04:00

We are just back from a productive trip to the mountain, spending 6 days at the summit glaciers. Typically, the dry season extends into October, but this year, rain and snow were a near-daily occurrence. One evening, snowfall accompanied by lightning and thunder collapsed our dining tent. Such variability keeps the work interesting!

Our primary objective was recovering data, changing-out instruments, and servicing the weather stations for another year of autonomous operation. For example, surface lowering of the ice (due ablation) required us to lower one of the stations further into the glacier. This was accomplished by considerable chiseling of ice, to create a one-meter deep hole. We also measured and re-drilled mass balance stakes, conducted GPS surveys, and re-photographed glaciers. This year we recovered 48 additional ice cores, which were kept frozen until reaching the laboratory freezer.

A selection of images from the fieldwork is below. For a day-by-day account of the adventure, check the "Kibo2011" group on Facebook. Additional images can be seen here.

Special thanks this year to Carsten Braun (Westfield State University), Tanzania National Parks, the Tanzania Wildlife Research Institute, and to Simon and crew at Summit Expeditions and Nomadic Experience (SENE). All were extremely helpful, for which we are most grateful.

Image #1 (above). Northern Ice Field margin.

Image #2. Kersten Glacier, just below Uhuru Peak. One year ago the upper and lower sections were still connected!

Image #3. Little Penck Glacier, continuing to retreat and now clearly separated into two parts.

Image #4. Northern Ice Field (distant) and the two sections of Furtwängler Glacier (foreground). Compare the Furtwängler image with that from 2002 (click here).

Image #5. One component of the UMass station, including instruments compatible with the U.S. Climate Reference Network (CRN). Note mass balance stake to left.

Image #6. The original UMass AWS, with Uhuru Peak in distance. Barely visible against the rock background is the "RimeCam" - acquiring 3-hourly images to help assess measurement quality.

Image #7. Swiss collaborators from Paul Scherrer Institute working through heavy snowfall, coring the Northern Ice Field's vertical wall. Our objective here is refining the history (chronology) of glaciers on Kilimanjaro.

Image #8. A less-fortunate visitor to Kibo's glaciers... reminding us how important safety is at nearly 6,000 meters elevation.

August Update

2011-08-19T09:02:00.002-04:00

This pair of images provides a glimpse of how the Northern Ice Field has changed over the past ten months. Last week the surface was relatively flat (left), and ~70 cm lower than when penitentes covered the glacier in October of last year (right).

October's penitentes were the result of sublimating snow from the previous wet season (i.e., masika or long rains, March-May 2010). Subsequently, little snow accumulated during either the 2010 short rains or the 2011 long rains (although there was an important event in February, see details). Less snow results in higher net radiation at the glacier surface, leading to ablation.

The right-hand image shows the AWS after repositioning the tower into the ice; note the lowest of the three enclosures, gray in color with the blue strap barely visible. Ten months later the same enclosure is well above the surface, with nearly half the tower base section exposed.

Paradoxically, the glacier surface appears relatively bright in the August image (i.e., high albedo). Two observations help account for this, and indicate why there hasn't been even more than 70 cm ablation. The first is a SPOT satellite image from 17 June (courtesy Nicolas Cullen) showing partial snow cover within the crater. This snowcover - likely to an even greater depth on the glacier - may have been residual from the long rains and/or the result of snowfall only 8 days earlier, a relatively uncommon event in June. The second observation is from the photographer of the left-hand image, Dr. Clavery Tungaraza (Faculty of Science, Sokoine University of Agriculture in Morogoro, Tanzania). In crossing the crater on 8 August, he reported walking through ~15 cm of snow showing no signs of melting, in dry, very cold weather. Again, some of this snow may have been residual, and some may have been associated with a couple small snowfall events during July. The very next day, as Clavery was desending, telemetry from the AWS indicates a multiday snowfall event began!

Nonetheless, dark old ice is just beneath the mantle of snow or superimposed ice creating the bright appearance in last week's image. In another two or three months, it is quite possible that the one-year net loss of ice from the Northern Ice Field surface may amount to a meter or more. This would make 2010-11 among the most negative years since 2000, perhaps not surprising in the context of drought impacting the Horn of Africa just to the north.

[UPDATE 9/4: The snowfall event mentioned above continued from 9 to 15 August and resulted in net accumulation of ~5 cm. This brightened the glacier surface and temporarily suppressed ablation for a week. Net surface lowering for the month was similar to July at ~8 cm.]

Kilimanjaro Glaciers

2011-08-05T15:29:00.001-04:00

Just over a century ago, glacier ice encircled the summit crater of Kilimanjaro, with perhaps only the inner Reusch Crater free of ice. (On the image above, the Reusch Crater is the middle, or second largest, of the three depicted. For scale, it is ~800 m in diameter.) Although their areal extent is now greatly reduced, as evident on this July 2009 image, the glaciers remain both beautiful and scientifically fascinating.

I wrote an overview of the mountain's glaciers that has just been published by Springer, as a contribution to their new Encyclopedia of Snow, Ice and Glaciers. The Kilimanjaro chapter briefly describes the history of glacier research on the mountain, and describes what makes these ice masses unique. It is available here.

Dry Season Ablation

2011-07-29T20:11:00.002-04:00

Dry conditions continue at the summit, likely reflecting dryness on larger and longer time/space scales. Telemetry from the weather station reveals only 3-4 snowfall events since October, with the largest being that in mid-February as previously noted. One minor snowfall of a few centimeters in June served to brighten the surface slightly, enhancing reflection of solar radiation. Nonetheless, the surface lowered by ~5 cm during June and has increased this month.

Just north of the Kilimanjaro region, drought conditions are contributing to severe famine, with over 10 million people in need of humanitarian assistance. Although suffering and displacement are greatest in Somalia, large areas of Ethiopia and Kenya are struggling with food insecurity. A map posted on the Reliefweb site shows the geography of the problem as of mid-July; Kilimanjaro is just south of Kenya's southernmost Emergency Zone on the map. Another graphic from the Famine Early Warning Systems Network provides further details.

[UPDATE 8/8: NASA's Earth Observatory website has been covering the developing drought since last autumn when rainfall was below normal, and has posted a series of SPOT and other images. There is also an overview discussion on how the tropical Pacific is involved, through La Nina teleconnections.]

Synopsis of 2010-11 wet seasons

2011-06-02T14:14:00.001-04:00

By the first of June an extended dry season is typically underway at the summit of Kilimanjaro, one of the most reliable features of a climate with considerable interannual variability. In a regional context, this dry season follows the "long rains" (Masika) which generally encompass much of the 3-month interval March through May. A second, shorter wet season (Vuli) happens in November-December and is somewhat more variable in magnitude and timing.

This year, neither Vuli nor Masika resulted in net accumulation, which will likely result in tremendous ablation on Kilimanjaro's horizontal glacier surfaces during the next 5-6 months. Just how little accumulation was there? Well, between 1 Nov. and 1 June (encompassing both accumulation seasons), a 30 cm net lowering of the Northern Ice Field was very consistent between the two sensors (i.e., -28 and -32 cm). For the same interval of 2009-10, the surface increased by over 60 cm.

During the brief dry interval between Vuli and Masika (usually occurring during January and/or February), ablation also predominated, except for one snowfall event detailed earlier that turned out to be the largest snowfall event of either 2010-11 wet season, and the largest since the previous May.

More humid... but no accumulation for March

2011-04-05T11:15:00.000-04:00

During March, there was no snow accumulation on the Northern Ice Field. Telemetry indicates a couple minor snowfalls which weren't recorded by both of the ultrasonic sensors, and then an event of 5-10 cm on 18 and 19 March. Nonetheless, the average net change in surface height amounted to 0.0 cm.

Atmospheric humidity increased during the month however, so accumulation during April and May is more likely. This is the typical pattern, as the long rains (Masika) get underway with passage of the ITCZ over the region (see here, for example). February is rather dry on average, relative to the prior 3 months (NDJ), with the mean vapor pressure increasing 0.2-0.3 hPa from February into March. This year, the mean relative humidity increased by 20 percent; vapor pressure data are not yet available.

new video

2011-03-21T12:41:00.002-04:00

Here is a new video produced by Caleb Medders at NBC Learn about glacier recession in general, including some brief thoughts on Kilimanjaro.

Snow!

2011-02-21T12:01:00.001-05:00

A 3-day snowy interval was underway at this time last week, bringing over 50 cm of snow on Tuesday to Lava Tower camp at the 4,600m level - and ending an extended dry period. This snow required some climbers to turn back, according to Simon Mtuy at Summit Expeditions, as continuing up the mountain became too difficult. We hope to post photos of the event here shortly.

At the summit, snow began accumulating on Sunday the 13th and continued into the 16th. Telemetry indicates that the event brought somewhere between ~19 and 28cm to the glaciers. Through noon today (local time) the new snow had settled and ablated by 5-10cm, over the past ~5 days.

Hopefully this snowfall brought much-needed rainfall to northern Tanzania. Perhaps the "long rains" are beginning, a bit early?

[UPDATE 3/4: Below are a couple images as the event was beginning. The first illustrates slight accumulation around the two stations on the first day of snowfall. The lower image is a view of Birafu Camp on the second day. The heaviest snowfall came the next day, which some guides describe as the most they can recall in ~4 years. Both images courtesy of Clavery Tungaraza]

Weather station images

2011-01-20T22:22:00.001-05:00

Here is a link to October images of Kilimanjaro's weather stations. Penitentes were present at the time on most glacier surfaces, and these appear in the images. Depending upon their size, penitentes can make glacier travel rather difficult. On Kibo it is unusual to find them greater than about 0.5m in height, but in the dry Andes they develop to heights of several meters. Currently the glacier surface is likely to be much flatter, as ablation continued through what normally are the wet months of November and December.

Little snowfall to the Solstice

2010-12-21T15:53:00.000-05:00

The 'short rains' typically bring snowcover to the summit crater by the Solstice, but not this December. One event during the second week resulted in ~10 cm of accumulation on the glacier. This was followed by drier weather, so quite likely the crater is now largely snowfree. Any first-hand observations from the summit during the holidays are welcome!

Timelapse: watch 129 days in 11 seconds

2010-11-18T22:43:00.001-05:00

In early 2005 we installed a timelapse camera system near the weather station, with objectives of visually documenting the variability of weather (esp. clouds), glacier surface texture & roughness, accumulation & ablation, and crater snowcover. Images demonstrate the pronounced and typical diurnal cycle of convection on southwestern slopes, as well as interesting variability within the seasonal cycles.

A movie of 129 days worth of images is available here, spanning 8 Oct. 2009 to 14 Feb. 2010. To provide consistent lighting, these images are all from 6 PM local time, when the upper Breach Wall and the Furtwängler Glacier are illuminated. To fully appreciate the day-to-day variability of weather and snowcover depicted, try watching just one portion of the image (e.g., convection to the South, glacier in foreground).

The two images below are from the same time interval, illustrating dry conditions on a clear day, and fresh 'short rains' snowcover (respectively). Note the white ablation stake in the foreground; 42 cm was exposed in early October of 2009 (shortly prior to date of upper image), increasing a year later (8 Oct. 2010) to 120 cm.

2010 dry season ablation

2010-11-03T11:20:00.000-04:00

June through October is typically an extended dry period at the summit of Kilimanjaro, with ablation of horizontal glacier surfaces often increasing once the seasonal snow cover is gone. During September and October this year, ablation was especially pronounced on the Northern Ice Field, despite above-average snow cover at the end of May. Ablation will continue at this pace in November until the 'short rains' begin and snow cover is restored.

To illustrate, average net surface lowering at the weather station (2 sensors) was 30 cm in both October and September, following 19 and 22 cm in August and July, respectively. New records were established for net ablation over 2-, 3-, and 4-month intervals (since 2002).

Analysis of October 2010 field measurements is just getting underway, including those from a network of ablation stakes, but it appears that surface ablation may have been more normal on the southern glaciers. With our Innsbruck colleague's full instrumentation on that side, it will be fascinating to further investigate these spatial patterns of mass and energy flux.

Success!

2010-10-21T12:01:00.000-04:00

Back safely from fieldwork at the summit. Thanks to Simon (above) and the SENE crew (Summit Expeditions & Nomadic Experiences), as well as the Marangu Hotel team, this was a fun and productive trip. Over the course of 6 busy days amidst the penitentes, we accomplished just about every objective on the list; details will be posted soon.

Upcoming fieldwork

2010-09-10T12:51:00.012-04:00

I haven't been on the mountain for 11 months now, and am anxious to get back. Telemetry indicates that the rate of ablation during the current dry season has been unprecedented in the 10-year record - which is somewhat perplexing. Snow accumulation began on the glaciers within a few weeks of our October 2009 fieldwork and continued without much interruption until the very end of May, bringing a net accumulation of 70 cm to the Northern Ice Field. Ablation then began, and although measurements from the two sensors differ, most of this snow appears to have now ablated. Visiting the glaciers will allow evaluation of the extent to which melting, evaporation, and superimposed ice formation is responsible.

So, we depart later this month for the summit glaciers with an ambitious program and a collaborative team, including personnel from the Univ. of Massachusetts, Innsbruck University, and NASA JPL. Simon Mtuy and Summit Expeditions are again providing logistical support on the mountain. One of my objectives will be to add reference-quality instrumentation developed by the U.S. CRN (Climate Reference Network), establishing the first CRN station outside the Americas. Operating CRN instruments alongside those which have been on Kilimanjaro since February 2000 will provide an intercomparison with which the long-term data can be adjusted. Measuring air temperature in that environment, on snow and with solar radiation typically exceeding 1,200 W/m^2, is far more difficult than might be expected.

Accompanying work at the weather station will be measurement of how ablation on the glacier has varied spatially, while NASA team members investigate microbiological diversity in the ice. And we're optimistic about getting some dates soon on ice samples collected last October. Stay tuned!

-Doug Hardy, UMass Geosciences

Science journalism

2010-08-26T15:10:00.000-04:00

Christopher Reddy of Woods Hole Oceanographic Institution has an opinion piece in the August 25th Wall Street Journal, pertaining to media coverage of the Deepwater Horizon's subsurface oil plume. Although the situation is arguably more complex and important than the Kilimanjaro retreating glacier story, I find it to be an interesting analog in terms of scientist's differing findings, their interaction with journalists, and how the story is conveyed by the media. Reddy suggests that "...it is incumbent on scientists and journalists to keep the results in perspective" [especially those which are preliminary] "and refrain from veering into misleading waters."

Two new publications

2010-07-23T10:14:00.002-04:00

This week, two new papers add to our knowledge of Kilimanjaro's glaciers. Georg Kaser is first author on "Is the decline of ice on Kilimanjaro unprecedented in the Holocene?" published (appropriately enough) in The Holocene. The paper sets forth a hypothesis that the glaciers may be only hundreds of years old, rather than 11,700 - as detailed in the only other paper published on the matter (Thompson et al., 2002). A link to this new paper, as well as the 2002 paper in Science, are provided to the right. The quest for definitive dates on the ice is underway!

A second new paper is primarily the work of Ph.D. student Michael Winkler (Innsbruck), and published in Erdkunde (in English). "Land-based marginal ice cliffs: focus on Kilimanjaro" will be of interest to anyone familiar with - or intrigued by - the unique vertical walls of Kilimanjaro glaciers. The paper is also available from our publications link.

Dry season underway

2010-07-07T22:31:00.000-04:00

As typically the case, the beginning of June marked the transition from accumulation to ablation on the Northern Ice Field. Two sensors are used to measure changes in surface height, and while one indicates less than 5 cm of ablation the other shows 20-25 cm (with the average being -11.5 cm). In both cases the decrease is more-or-less continuous through the month.

Whimpy Long Rains

2010-06-16T11:10:00.001-04:00

Telemetry from the Northern Ice Field suggests that the Long Rains ended at the end of May, consistent with previous years. Snowfall frequency was fairly regular, beginning with a relatively large event in March (see this entry), but net accumulation was only 10-15 cm. This is quite a contrast to the Short Rains of November to mid-January which netted 45-50 cm of accumulation on the glacier.

The dry interval between the rains this year was centered on February, as is typically the case. It extended from mid-January to the March snowfall mentioned above, yet included 2-3 multi-day snowfall events of 5-10 cm.

In summary, as of today (mid-June) snow depth on the Northern Ice Field is ~60 cm.

Kilimanjaro returns to PNAS

2010-04-23T09:33:00.001-04:00

Back in November, we published a paper in Proceedings of the National Academy of Science (PNAS) which documented changes in ice-covered area on Kilimanjaro since February 2000 (see blog entry with link to paper). Collaborators at the University of Innsbruck had a different perspective on a few elements of the paper, so wrote a Letter to the Editor. Together with our response, the letter was published online April 21st in PNAS Early Edition, and both will remain there until appearing in print.

The Mölg et al. letter is also available here, and the Thompson et al. response is here.

As an active collaborator with all authors involved, I would like to point out that such discussion - in scientific literature - is normal, healthy scientific discourse. This is how the process is supposed to work, and this is one way in which science advances! Our correspondence does not demonstrate uncertainty about whether Kilimanjaro's glaciers are shrinking, or whether they are likely to disappear with a few decades, or whether global warming is likely driving recent shrinkage; we are all in complete agreement on these tenets! Nor do the letters reveal some fundamental divide between research groups. In both cases, dedicated researchers are simply articulating nuanced perspectives gained from varying combinations of arduous fieldwork, laboratory analysis, and/or computer modeling. Given the short history of quantitative measurements from Kilimanjaro, both groups are attempting to make sense of climate-glacier interactions that all agree are complex. Everyone involved is dedicated to developing a better understanding of the mountain's fascinating glaciers.

-Doug Hardy, UMass Geosciences

Singing at the summit

2010-04-09T09:29:00.001-04:00

Here are a few audio recordings from the cook tent, by the singing crew of October 2009 (above). Only those who ascend slowly with good equipment are capable of such joyful singing at nearly 6,000 meters. Thanks to everyone at Summit Expeditions!

cook tent track #1
cook tent track #2
cook tent track #3
In Mbahe, track A
In Mbahe, track B
In Mbahe, track C

Long Rains begin

2010-04-01T12:06:00.000-04:00

Here is an out-the-car-window shot of Kilimanjaro from 21 March (courtesy Michael Winkler, Innsbruck Univ.), with a mantle of fresh snow. Michael departed from a snow-free crater on the 19th. By the 21st, my telemetry data from the Northern Ice Field does not indicate accumulation (cf. this south-side view), suggesting that snowfall was primarily on the south side. This asymetry is typical of snowfall during the Long Rains (March-May). However, appreciable snowfall on the Northern Ice Field did begin in the evening of the 22nd and continued at least into the 23rd; additional smaller events continued sporatically up to today. On the 27th, Timba from Ahsante Tours & Safaris wrote that in Moshi it was "pouring big time" and that the "mountain has been on an all time white look since last week." He says that "the SE prevailing winds have begun" and the long rainy season is in "full swing."

Long Rains beginning?

2010-03-08T14:34:00.000-05:00

After a brief dry interval, telemetry shows that snowfall is again occurring at the summit of Kilimanjaro. Could we be seeing the beginning of the "Long Rains"? Contributor Timba at Ahsante Tours & Safaris writes of "heavy rains in Moshi and surrounding areas yesterday. In town [and on the mountain], it rained the whole afternoon to early evening." Timba suggests that the normal long rain pattern is for morning rain in Dar es Salaam, followed by afternoon and evening rain in the Kilimanjaro region, but his friend in Dar saw no rain yesterday. Stay tuned.

Ten Years!

2010-02-24T22:49:00.000-05:00

Here we are, exactly 10 years ago this morning, after installing the AWS on Kibo's Northern Ice Field (1300 UTC or 8 am EST, 24 February 2000). Hard to believe it has been that long -- or that it function so reliably. Thanks to everyone involved in keeping the measurements going!

Kilimanjaro from space

2010-02-12T08:33:00.003-05:00

Kibo (left) and Mawenzi (right) from the International Space Station on 21 January at ~10am (click to see larger). Note convective clouds just beginning to form to the southwest, as happens daily at this time. Although the crater is snow-free, considerable snowcover is visible on the north side of Kibo; only the brightest-white areas are glacier ice. [Image ISS022-E-33592, courtesy of Earth Sciences and Image Analysis Laboratory, NASA Johnson Space Center]

"Current weather" update

2010-02-11T20:50:00.000-05:00

Shortly after the first of each month we provide a synopsis of current conditions at the summit, based upon data received by telemetry and processed in the UMass Climate System Research Center. However, we have been without a programmer to run the scripts since mid-December, and apologize to those who look forward to these updates.

The most recent data were accessed today, and the station looks to be working well. Here is what the partial recovery indicates: from 1 December until mid-January, net snowfall amounted to at least 22 cm. If we can obtain early January data from the Argos archive, it may show the total to be even higher. For the entire "short rain" period, net snowfall was at least 46 cm, which is not a record but certainly above average.

Hopefully a synopsis for February can be posted on 1 or 2 March.

Rains continue to the West

2010-01-04T12:39:00.002-05:00

Here are a couple notes about rainfall to the west of Kilimanjaro; seems like the short rains have been quite good!

Dec. 28th (Marc Baker): "Just back from the wettest Serengeti in 10 years, first time I have had to abandon two vehicles after two days of constant rain in Piaya."

Jan. 2nd (Jo via Neil Baker) summary of Serengeti and Ngorogoro lakes:
Lake Magadi ngng - full
Malanja depression - filling fast
Olbalbal depression- full and overflowing
Lake Manyara - filling fast
Engaruka depression - nearly full

[UPDATE 1/6 (from David Bygott): Lake Natron also full, raining heavily in Zanzibar]
[UPDATE 1/7 (from Chris Schmeling): Lake Eyasi close to full; 88mm precip. already this month]

AGU award to Thomas Mölg!

2009-12-16T10:08:00.001-05:00

Congratulations to Dr. Mölg on receipt yesterday of AGU's 2009 Young Investigator Award. Thomas has been an invaluable Kilimanjaro collaborator since July 2002, when he joined Ray Bradley and myself on the mountain. Details of Thomas' selection, his bio and publications are here (along with a link to award ceremony video).

-Doug Hardy, UMass Geosciences

Persnickety or seeking truth?

2009-11-24T11:03:00.006-05:00

Earlier this month we published a paper in the Proceedings of the National Academy of Science (PNAS) detailing changes in Kilimanjaro's ice area and thickness since 2000. This is essentially an update on our 2002 paper in Science, and I am the only non-OSU co-author. Considerable media interest followed, as typical for anything new on Kilimanjaro glaciers.

Was this paper reported differently than the 2002 paper? My impression in that many traditional media outlets simply reproduced the Ohio State University Press Release (Lonnie Thompson is first author), rather than using journalists to ask probing questions; much cheaper!

In the aftermath, blogs are discussing how this paper was reported. For example, Tom Yulsman in the Univ. of Colorado Boulder's Center for Environmental Journalism has created an assignment in which students read and analyze the PNAS paper and it's media coverage! And Cruel Mistress has critiqued Sindya Banhoo's article in the NY Times. Andy Revkin got such discussion underway with a NY Times piece back in 2004.

Anyway, another article on issues pertaining to the PNAS paper was published yesterday in the Daily Hampshire Gazette. Journalist Kristin Palpini details my perspective on the research and it's impacts in the media. Although there are a few errors in the article, she does a nice job of illuminating the "debate." As continuing Kilimanjaro discussion in the blogosphere reveals, details are important!

[UPDATE 12/16: The future of science journalism is discussed in a couple articles published this week, at PoynterOnline and at Nature News. In the Poynter piece, Natalie Angier (NY Times) notes that "coverage tends to be more fragmented and less comprehensive than it once was" and Charles Petit (Knight Science Journalism Tracker) "doesn't recall seeing very many investigative science pieces..." The article by Mallary Jean Tenore references a July 2009 Pew study which "found that 76 percent of scientists surveyed say news reports don't distinguish between findings that are well-founded and those that are not." And in the Nature article, Andy Revkin discusses how the "role of journalism is definitely shrinking."]

[UPDATE 1/7: Jack Williams' blog entry yesterday has a nice discussion of the problem mentioned above, following some thoughts about low temperatures across the eastern U.S.]

-Doug Hardy, UMass Geosciences

Snowfall continues

2009-11-16T08:35:00.000-05:00

Consistent with the regional rainfall picture, Kilimanjaro's summit is seeing day after day of snowfall. Last week the Northern Ice Field saw another ~10 cm of snow accumulation!

Short rains begin

2009-11-04T10:41:00.001-05:00

On the Northern Ice Field, snow began accumulating on 26 October as the regional "short rains" got underway. Timba at Ahsante Tours & Safaris reports that Kibo was white on Monday Morning (2 Nov.), and telemetry shows that by Tuesday morning 8 cm blanketed the glacier at the AWS.

So for the 2009 dry season, between the last snowfall in mid-June and the end of October, surface lowering at the Northern Ice Field weather station was 52 cm. This amount is not atypical, as the short rains have come more-or-less on schedule. However, since the dry period on Kilimanjaro began in June 2008, ablation has been quite exceptional - over 1.5 meters of ice. An interesting perspective on the East African drought's cumulative impact - just prior to the short rains - can be seen on NASA's Earth Observatory website. Now, in this El Nino year, flooding has become a problem further north in Kenya.

-Doug Hardy, UMass Geosciences

Snow!

2009-10-29T14:19:00.003-04:00

The long dry interval at the summit is over, and snow is again accumulating for the first time since mid-June. Our recent fieldwork aspired to visit the glaciers just before the short rains began, and it seems that our timing worked out. After descending on the 9th, we experienced a heavy, extended rain event the next day at Mbahe (near Marangu). Humidity remained high that afternoon at the AWS, with possibly a dusting of snow. Then snow and sustained high humidity was recorded on the 15th and 16th; during this time Simon reports spending a "hot night" in the crater (i.e., thick cloud cover). AWS measurements show that the wet season really got underway this week on Monday. Telemetry through this morning shows that snowfall continued through Tuesday and Wednesday, with a net of ~4 cm. This is enough to bring the glacier surface albedo up by 20-30 percent!

Fieldwork photos

2009-10-29T13:25:00.001-04:00

Here is a link to photos taken on the mountain during Sep/Oct fieldwork. With very little seasonal snowcover due to the drought, we had a rare opportunity to observe glacier margins and ice features. Over the course of a week at the summit, we attended to the automated weather station (AWS), offloaded data from other dataloggers, measured and redrilled ablation stakes, and collected basal-ice samples for dating.
OCT. 2009 PHOTOS

A week at the summit

2009-10-14T13:57:00.002-04:00

Just back from fieldwork on the summit glaciers, between 3 & 9 October. Conditions were very dry, allowing us to observe processes un-hidden and un-influenced by snow. Varying weather conditions beautifully demonstrated how sublimation and melting fluctuate in their dominance, even on horizontal surfaces. We came across ablation stakes not seen since 2001 - along with a few surprises buried for perhaps centuries. More photos to follow soon!

-Doug Hardy, UMass Geosciences

Meltwater Runoff

2009-10-01T18:00:00.006-04:00

From Karanga camp on Kilimanjaro (4025m), Doug and Mark Jonas made an important observation today via text msg: "Extensive ribbons of ice were seen below all of the south slope glaciers; flowing water could be seen even without binoculars from ~3km distance, and was clearly heard." They are anxious to see conditions at the summit. [Late October update: listen here to a recording of this distant meltwater runoff (with White-naped Ravens)]

October fieldwork

2009-09-18T12:23:00.005-04:00

Yes... a chainsaw! We depart next week for fieldwork at the weather station and on the glaciers. Conditions at the summit are currently very dry, as elsewhere in East Africa where the drought has brought hardships to many (BBC slideshow). With little snowcover, we will be mapping the pattern of albedo and ablation on the glaciers, and collecting ice samples for 14C dating - a collaborative effort with Margit Schwikowski at Paul Scherrer Institute in Switzerland. Obtaining ice samples and keeping them frozen all the way to Switzerland will not be easy! Cutting them from the glacier will employ a powerful, lightweight battery-powered saw made by Troy-Bilt, with no noise and no emissions. Testing of this newly-available saw has been very encouraging. [Late October update: listen here to this chainsaw in action, cutting glacier ice!]

The left-hand image illustrates the sampling opportunity these glaciers provide (vertical dimension shown ~30m). Updates on the fieldwork, with photos, will appear here in mid-October.

Important new paper

2009-08-15T11:30:00.002-04:00

Want the most up-to-date details on Kilimanjaro's glaciers and climate? A paper published Monday in the Journal of Climate is a good place to start. Thomas Mölg is first author, with input from the rest of us working together on this issue since 2002; the title is "Quantifying climate change in the tropical midtroposphere over East Africa from glacier shrinkage on Kilimanjaro." Important insights emerge from spatially-distributed mass balance modeling, replete with enough sensitivity testing to satisfy even those skeptical of this approach.

The crucial role of atmospheric moisture variability on glacier mass balance is demonstrated once again (esp. precipitation dependency), along with many other interesting results. Most encouraging is the indication that further study of glacier retreat on Kilimanjaro will move us toward a better understanding of why equatorial East Africa continues to become drier -- a question of great societal and environmental importance.

Access the paper here.

Another wet season fails

2009-06-02T13:10:00.003-04:00

In the last 10 years on the Northern Icefield, the "long rains" have ended by the first of June. If this holds true for 2009, a second consecutive wet season has failed. The 12-month interval prior to 1 June has been the "driest of the century" by far, with a net glacier-surface lowering of 1.3 meters at the weather station. As this volume of ice has evaporated and melted, dust has been concentrating at the surface, augmenting that present before the late-2006 snowfalls. And with snowfall unlikely over at least the next 4 months, the rate of ice loss could exceed that ever witnessed.

Mid-month snow

2009-05-19T10:46:00.002-04:00

On 11 May, snow began accumulating on the Northern Icefield. Through this morning there has been ~4 cm of net accumulation. Not much in the context of most mountain locations - but enough to raise albedo considerably on the glaciers. Hopefully the event will continue for another couple weeks; Juliana Adosi at the Tanzanian Meteorological Agency tells me that the long rains are forecast to end at the end of the month.

-Doug Hardy, UMass Geosciences

Manuscript flurry

2009-05-19T09:21:00.003-04:00

Three papers on Kilimanjaro glaciers have been submitted within the past month, and are now in the review process. The sole-authored encyclopedia entry provides a comprehensive overview of the glaciers characteristics and processes. The other two take rather different perspectives and will be sure to stimulate discussion. Stay tuned!

Submitted to The Holocene: Is the decline of ice on Kilimanjaro unprecedented in the Holocene? (Georg Kaser, Thomas Mölg, Nicolas Cullen, Douglas Hardy, and Michael Winkler).

Submitted to Springer’s Encyclopedia of Snow, Ice and Glaciers.: Kilimanjaro. (Douglas Hardy).

Submitted to Proceedings of the National Academy of Sciences USA (PNAS): Glacier Loss on Kilimanjaro Continues Unabated. (Lonnie Thompson, Henry Brecher, Ellen Mosley-Thompson, Douglas Hardy, and Bryan Mark).

In the beginning, there was Carlos

2009-05-08T13:40:00.013-04:00

The beginning of our work on tropical glaciers, that is. Carlos Escobar was our guy in 1996 as we set out to begin climate research on Volcan Sajama in Bolivia. Not just to reach the summit at 6,542 m, not just to camp there for days, but to operate the world's highest-elevation satellite-linked automated weather station. Carlos made it happen and kept it fun, first on Sajama, then on Illimani... the consummate guide who became a friend to us all. And the help and friendship came not only from Carlos, but the whole Escobar family, especially brother Jose Mauro, wife Grissel, niece Monica, Mateo and his other children. International projects can't happen without people like Carlos, who solve the problems and make all the stress of high-elevation research worthwhile.

Today, Carlos passed away after struggling for months with brain cancer. Carlos, our Guía Internacional de Montaña, co-author, Everest summiter just 3 years ago this month, and buen amigo. Compounding the normal emotions is a terrible feeling of helplessness; for all Carlos and his family provided us, not being there to help in such a difficult time is painful...

To all the Escobars, know that all who worked with Carlos and your family are thinking of him, and you. Memories of him live on with each of us. Be strong, live strong...

Doug and the UMass crew

Long rains late

2009-05-06T16:08:00.001-04:00

April was another month of net ablation. There was a small snowfall event which began late in March (see 4/10 entry below), but otherwise there was only a few cm on ~21 April.

May could turn out to be snowy however, as it did in 2003 and 2007 following dry March and Aprils. Conversely, the long rains were finished entirely by this time in 2002, 2004 and 2006 - and failed completely in 2000.

At any rate, for the previous 12 month interval, mass balance on the Northern Ice Field has easily been the most negative of the decade.

Journal of Climate paper

2009-04-15T13:24:00.001-04:00

A new paper has been accepted for publication in the Journal of Climate titled "Quantifying climate change in the tropical mid troposphere over East Africa from glacier shrinkage on Kilimanjaro" with authors Thomas Mölg, Nicolas Cullen, Douglas Hardy, Michael Winkler, and Georg Kaser. This group has been collaborating for several years; most are part of the Tropical Glaciology Group at the Univerity of Innsbruck.

The paper examines 19th century recession of the southern-slope Kersten Glacier, by backward modeling with a spatially-distributed mass-balance model. Results indicate that late-19th century precipitation was higher by +160 to +240 mm/yr, dominating the mass budget and producing a larger glacier extent. Today, the Kersten Glacier terminus is ~600 m higher in elevation, and the glacier is loosing mass at ~500 kg/m^2/yr.

-Doug Hardy, UMass Geosciences

Another dry month

2009-04-10T09:15:00.002-04:00

Little snowfall on the Northern Ice Field between mid-February and 28 March, satellite telemetry indicates. Only one mid-month event of 2 cm. Then, a snowy interval 28 March to 2 April bringing ~6 cm of accumulation. Six centimeters isn't much, but it is enough to substantially raise the albedo and keep it elevated for several weeks. Hopefully more snow will follow...

-Doug Hardy, UMass Geosciences

2009 Long Rains...

2009-04-08T09:10:00.000-04:00

seem to be late. Normally, the wet season is underway by now. Through most of March this year, however, conditions remained dry. Very soon we will post a synopsis of measurements on the weather page. Normally this page is updated on the first or second of each month, but we're late this month due to personnel changes in the UMass Climate Center.

Still dry - mid-February

2009-03-30T19:12:00.001-04:00

"light dusting of snow" at the summit (1-3 cm), February 16

- Hassan Basagic, Portland State University

January fieldwork

2009-02-01T12:00:00.005-05:00

Only four months since my last trip up, and time for another... unplanned and unbudgeted! The September trip was largely successful, especially in terms of Northern Icefield work. Over the course of 5 days the weather station received a complete service, including change-out of several key instruments, lots of mass balance stakes were visited, and there was time for several GPS surveys. Although a medical emergency precluded visiting the southern glaciers, most objectives were completed and we were hoping that the 'short rains' would begin soon.

No such luck. The 2008 short rains utterly failed, both on the mountain and regionally. In conjunction with conflict earlier in the year, this lack of rainfall brought great hardship to eastern Kenya. By mid-January, Kibo's summit had not seen subsantial snowfall since early June, so very low surface albedo was causing considerable absorption of solar radiation. The impact? Mass loss from horizontal ice surfaces - lots of it! Satellite telemetry from the station revealed a grim reality, that measurements were in jepeordy without a trip to reset (lower) the tower down into the ice (cf. New York Times, Feb. 2001).

Fortunately, collaborators from Innsbruck had been planning a January 2009 trip for several months, and were kind enough to let me piggy-back onto their logistics. This trip was based from the Marangu Hotel's peaceful setting, and their staff supported our effort on the mountain. We spent only 4 nights going up, a bit less than I've found optimal, and then 3 at the summit.

No snow was visible on the mountain from Marangu, or from the east side as we drove around to Rongai - conditions more typical of August. Thereafter though, every day of our trip featured rain and/or snow and/or thunder, except, paradoxically, our final descent through the rainforest.

At the summit, ablation since September was readily apparent. A thin mantle of new snow (5-10 cm, accumulating daily) partially obscurred dirtier ice surfaces than I'd seen in years (see image above). Some horizontal ice surfaces are now quite old (decades to centuries), with high dust concentrations causing low albedo. In just 4 months, ablation had reduced ice thickness by a meter in some places! On one glacier, 7 of 8 mass balance stakes had ablated out, and drilling new holes on 3 different glaciers occupied a chunk of my time. However, work focused on lowering the tower; most of the job was done in just over 2 strenuous hours, thanks to help from Geoffry, Good Luck, Leoned, David and Samuel.

Descending from the summit glaciers in a snowstorm, we pondered whether the short rains were late in arriving, or the long rains were beginning early.

-Doug Hardy, UMass Geosciences