Snowcover within the Kibo
caldera may have reached an annual minima last week. The two-image
Sentinel-2 timelapse above shows the same area, five days apart.
The mostly cloud-free image on 4 November depicts the largest extent of
snowfree area for calendar year 2020. Nonetheless, note the extensive
snowcovered area east of the Northern Icefield and north of Reusch
Crater; this was evidently an area of higher accumulation during the
previous wet seasons. South of Reusch Crater, white areas within the
caldera are all patches of snow - with the exception of one remaining
fragment of Furtwängler Glacier, the east-west oriented body just south
of the extensive snowfree area. On the caldera's south side, snowcover
blankets the south-southwest facing slope and delineates the rim,
closely paralleling the trail from Stella Point to Uhuru Peak.
Encompassed within this area are the upper fragments of Kersten and
Deckens Glaciers, with less-continuous snow around the Rebmann Glacier.
Below the upper south-side glaciers is a steep, 100-150 m band without
snow, then patchy snow and the snowcovered lower fragments of the
Kersten and Deckens Glaciers.
Snow blankets the entire upper portion of the mountain on 9 November, as
visible in the second image (despite a thin cloud veil). This snowfall
event is "right on schedule" in terms of the precipitation climatology
for high elevations of Kilimanjaro. This would be a fascinating time to
be up there, for a survey of snow depth and spatial variability...
Thursday, November 12, 2020
Seasonal change
Sunday, October 25, 2020
Fires extinguished, snowcover continues to decrease
I hear from friends in Mweka
that wildfires on the mountain are now out, thanks both to some rain,
and hard work by personnel. They burned quite close to the Mweka (descent) trail, just above the upper forest line, a zone which has been severely impacted by fires and climate change in recent decades (see Andreas Hemp reference within this link). A helicopter pilot from Kenya was able to
provide valuable assistance to firefighters for several days.
Today's satellite image - and that of 20 October - shows considerable
cloud cover on the mountain, as expected at this time of year. A "hole"
in the clouds does reveal the caldera's west side, and much of the
Breach, to now be snowfree.
The next clear view of the mountain will be posted here. Will any
seasonal snow persist to the next period of accumulation? Stay tuned!
Thursday, October 15, 2020
Serious wildfires continue [updated]
This morning's Sentinel-2 image of Kilimanjaro reveals the seriousness
of fires burning since Sunday, high on the mountain (bands 12, 11, and
4). Reports suggest the fire was started accidentally along the Marangu
Route. Early reports from TANAPA expressed premature optimism that "the
fire is already under control" (14 Oct. via @tzparks), yet Minister of
Natural Resources and Tourism, Hamisi Kigwangalla, is quoted in the NY Times today: "the task is harder and bigger than it is thought to be".
On the false color image above, note the Reusch Crater. Snow and ice
appear royal blue, with burning areas in yellow-red. This is a very
serious, extensive fire! Smoke is visible being blown westward from the
fires, burning at an elevation above 3000 m. The dominant vegetation
type at this level is giant heather (Erica excelsa), which ecologist
Andreas Hemp describes as "an obvious fire sign" which "enhances the
fire risk, as even fresh Erica wood burns well". As highlighted in a
UNEP posting based on Hemp's work, "nearly 15% of Kilimanjaro’s forest
cover was destroyed by fire since 1976 and was replaced by Erica bush
which extended its total area by 5km2 (mainly downslope)."
The upper portion of the popular Marangu Route is shown in green,
passing Horombo Huts where some fire damage may have occurred. One
updated account today (here) quotes Minister Kigwangalla as saying that
yesterday's rebound "destroyed the Horombo Tourist Camp, including 12
huts, two toilets, and solar equipment". The mountain's primary descent
route past Barafu Camp is also shown, appearing to be threatened by both
fire and smoke.
We await first-hand reports from the mountain, and welcome any additional information.
[UPDATE 10/16: Our friend Timba (Travel Consultant in Moshi) sent a link depicting Carbon Monoxide concentration, via the Earth website. Although the screenshot below does not show the data well, note the value for Kilimanjaro of 13,116 parts per billion by volume (high enough to cause chronic problems with long-term exposure - from CO alone).]
Tuesday, September 15, 2020
Processes in opposition
Light accumulating snowfall is common at this time of year, as is its subsequent ablation within a few days. These opposing processes are especially critical for the glaciers as the dry season concludes, because albedo reaches an annual minimum while temperature, humidity, and solar radiation are all increasing.
In today's image (not shown), partially obscured by clouds, the dusting of snow seen above has completely ablated, and snowcover within the caldera is patchier yet.
While it appears that areas of snow will endure the dry season this year, failure of the short rains - or even a delayed onset - might yet ablate much of the lingering summit snow.
Wednesday, September 9, 2020
What Will Gadd learned on top of Kilimanjaro
Red Bull today released a fantastic new Will Gadd film, shot with a full crew during our pre-COVID February trip. The finished product (45 minutes) is about extreme sport, but also about the science of Kilimanjaro glaciers and climate change; it is well worth watching.
Will was a joy to work with - as eager to learn and share knowledge as he is to climb ice - and clearly articulates the responsibility we all have to reduce our carbon impact. Red Bull deserves major credit for broadening the scope of their productions. And, the stuff is tasty!
Director Tom Beard and the KEO Films crew did a wonderful job of editing, and eagerly accepted ideas to insure an accurate result.
Access the film here: <https://redbull.com/thelastascent> or here.
Wednesday, September 2, 2020
31 August snowcover
Snowcover continued to
decrease during the last 5 days of August, as the image below reveals
relative to that from 26 August (previous post). Change appears most
evident in the northwest corner of the caldera. Nonetheless, the extent
of snow at the summit remains more than average - with perhaps two
months remaining in the extended dry season.
Tourism on the mountain remains minimal, as the new Coronavirus pandemic
continues. For example, the Machame register book shows only 58
climbers departing for the normally-busy months of July and August.
Our friend Simon Mtuy and a large SENE team have been assisting in a
large clean-up operation. Over just two days, SENE staff collected 45
kilos of trash from the Machame Camp area. Simon reports that this week
there will be 400 crew from 16 companies helping in the clean-up, which
will include the Western Breach route and the Crater Camp area. Asante
sana!
Monday, August 31, 2020
Snowcover at the end of August
Snowcover in the caldera has
been decreasing through August, and is now at roughly 75% by area. The
image above was acquired by Sentinel-2 on the 26th. Although it now
appears possible to reach Stella Point without ascending on snow,
considerable snow remains in some places, such as to the east of the
Northern Icefield.
During the boreal summer months of June-August, when the sun is in the
northern hemisphere, less solar radiation is received on any slope
inclined to the south. Note the extent of snowcover remaining on the
mountain's southern slopes (above). This area coincides with
where the Southern Icefield used to exist - illustrated below during
Walter Mittelholzer's flight over the mountain in January 1930. Whereas most
of the white area in 1930 is snow over glacier ice, very little ice
remains on the south side in 2020.
(Preservation of seasonal snow on the south side is not solely a
function of aspect. The spatial pattern of snowfall on the mountain
between November 2019 and June 2020 is not known (and was likely not
uniform), and snowcover retention is also governed by the seasonal distribution and extent of cloud cover.)
Below: Mittelholzer's Fokker F.VIIb-3m "Switzerland" refueling enroute to Kilimanjaro [credit].