Climate and cryospheric changes within the Trans-African alpine zone:

1
Climate and cryospheric changes within the
Trans-African alpine zone scientific advances
and future prospects
Stefan Grab School of Geography, Archaeology
Environmental Studies University of the
Witwatersrand, South Africa
2
Objectives

• To briefly review high altitude African mountain
  research
• focusing on
• -climate
• -cryosphere
• - To identify potential research gaps
• - To review recent initiatives aimed at
  developing African
• Mountain research

S. Grab
3
Rationale why focus on African mountain climates
observed changes in freezing-level height are
related to a long-term increase in sea surface
temperatures in the tropics..tropical
environments may be particularly sensitive
because the changes in tropical sea surface
temperature and humidity may be largest and most
systematic at low latitudes (Diaz Graham,
1996, Nature)
Significance of African Mountains (with re to
climate) -High tropical representation -Extensiv
e latitudinal representation -Storehouses of
climate change -Refuge sites (human habitation,
fauna flora) -Important water reservoirs in a
drought prone continent
S. Grab
Climate change is impacting African mountain
systems Cryosphere hydrology ecosystems
economies - vulnerabilities
4
Ethiopian Highlands
Ras Dejen (4620m)

• What do we know?
• Climate of Simen (detailed measurements during
  the late 1970s by Hurni
• Climate of Bale (detailed measurements/description
  s by Miehe Miehe (1994) contemporary
  monitoring.
• Contemporary macro-scale seasonal climate
  forecasting work (e.g. Gissila et al., 2004)
• Long-term rainfall trends for highlands since ca.
  1897 (highest station 2750m)(Osman Sauerborn,
  2002)
• Quaternary climate change - based on proxy
  records (e.g. pollen)

S. Grab
1100000
Hurni Messerli, 1980 Institute of Geography,
Univ. of Berne
5
Ethiopian Highlands

• What is required?
• Archival based research for climate and cryogenic
  changes during historical times
• Evidence for past permafrost ?
• Timing of deglaciation in different regions ?
• Installation of atmospheric and ground climate
  monitoring stations in high mountain regions
  (Simen, Bale etc)
• Satellite based research (e.g. for monitoring
  contemporary snow cloud cover)

Saneti Plateau Bale Mnts
S. Grab
Dejen Escarpment Simen Mnts
S. Grab
6
Mt Kenya

• What do we know?
• Early 1900 descriptive climate and glacier
  records.
• Extensive work on sedimentary chronologies
  (moraine and lake sediments)(e.g. Mahaney 1970s
  1980s)
• Radiocarbon-dated lacustrine sed. sequences
  oxygen isotope records high resolution
  chronology of glacial advances / moisture
  balances during the Holocene (e.g. Karlén et al,
  1999 Baker et al., 2001).
• Regular glacier surface area / mass balance
  reports since 1980s (esp Hastenrath)
• Glacier reviews (e.g. Mahaney, 1989 Hastenrath,
  2005)
• Periglacial phenomena documented (including rock
  glaciers)(e.g. Hastenrath, Grab)

7
Mt Kenya

• What do we know.cont?
• High mnt atmospheric and ground climate studies
  (Winiger 1981 Grab et al., 2004).
• 1980s onwards CDE, Univ. Berne group agro
  climate hydro studies - plateau region around
  Mt Kenya.
• 1990s onwards Global WMO/GAW station at 3678m
  (MeteoSwiss Kenya Met. Dept) for standard
  meteorological data, CO O3 monitored since 2002.

8
Tyndal glacier (2004) Mountain Club
of Kenya
In Hastenrath, 2005
Tyndal glacier (1919)
(Arthur, 1921)
9
World Glacier Monitoring Service (WGMS) has been
published at 5 year intervals since 1959 Mt
Kenya has had a 67 ice reduction between
1899-1993 (WGMS, 1998)
10
Global WMO/GAW station Mt Kenya (3678m)
Mt Kenya

• What is required?
• Ensure continued climate monitoring at 3678m
  4200m. Reestablish the 4700m station near Point
  Lenana, adjacent to Lewis glacier.
• Borehole temperature monitoring.
• Detailed monitoring of Lewis glacier during its
  last phase of existence.
• Constraints Vandalism/theft

S. Grab
Global WMO/GAW station
Mt Kenya (4200m)
S. Grab
11
Kilimanjaro

• What do we know?
• Early 1900 descriptive climate and glacier
  records.
• Limited work on sedimentary chronologies
  (moraine)(e.g. Mahaney)
• Very limited periglacial research (possibly 2 or
  3 papers during 1970s)
• Regular glacier surface area / mass balance
  reports and reviews from sketch maps, photos,
  tacheometry (late 1950s) to aerial
  photogrammetry and Landsat Images (1980s
  onwards) (e.g. Klute, Hastenrath, Osmaston, Kaser
  et al.)
• Ice Core records and Holocene glacial chronology
  (Thompson et al.)

12
Kilimanjaro

• What do we know..cont?
• 2000 onwards continuous climate monitoring on
  northern Icefield (Hardy et al.)
• Chan et al., 2007 Intraseasonal precipitation
  variability on Kilimanjaro and the East African
  region and its relationship to the large-scale
  circulation, Theor. Appl. Clim.
• Recent current research programmes on solar
  radiation modeling, ice-radiation geometry,
  volcanic interference, historical glacier cover
  change (Kaser et al.)
• Volcanic activity (fumeroles/sulphur emissions)
  may have increased since late 1800s.

13
Kaser et al. 2004
Source http//www.geo.umass.edu/climate/tanzania/
jan07.html
14
Kaser et al. 2004
15
Kilimanjaro
Fumerole

• What is required?
• Ensure continued climate monitoring at the summit
  and at lower altitudes.
• Establish presence, distribution
  characteristics of permafrost.
• Bore hole temperature recording to 2m depths for
  possible CALM site (Circumpolar Active Layer
  Monitoring)(proposal submitted by Palacios
  Grab)
• Record periglacial phenomena and processes
• Monitoring geothermal activity (understanding
  geothermal heat sources)
• Establishing multicentury ice cap histories
  (Kaser team)

S. Grab
16
Ruwenzori Virunga (Albertine system)

• What do we know?
• Ruwenzori commentary on glaciers discussed
  occasionally
• 1950s Heinzelin
• 1950s-1960s Whittow, Osmaston
• 1970s- mid 1990 apparent gap
• 1996 review by Kaser Noggler
• post 2000 ongoing implications on hydrology
• (Kaser team, Taylor team, Italian team,
  Eggermont team
• Limited climate data
• Kabale (1867m)
• Karisoke Research Centre (3100m) 1979 onwards
• Sabinyo (Rurambo, 2500m) Kinigi (2200m) data
  for limited years
• Ruwenzori (current monitoring)
• Historical documents (early 1900s) describe
  environmental conditions.

Alexandra (5109m)
Dave Van Smeerdijk
17
Ruwenzori Virunga (Albertine system)

• What is required?
• Ruwenzori
• ongoing glacier work (Kaser, Italian groups,
  Eggermont et al.)
• Establish periglacial phenomena and processes
  (permafrost?)
• Establish CALM sites (if premafrost is present)
• Establish additional atmospheric and ground
  climate monitoring at high altitudes ( Karisimbi
  elsewhere?)
• Establish status of previously installed weather
  stations.
• Establish historical climate change in Ruwenzori
  (last 140 yrs Taylor)

Dave Van Smeerdijk
18
Drakensberg Maluti system

• What do we know?
• Substantial cryogenic (periglacial glacial)
  research since the mid 1930s (ca. 70
  publications)
• Several short term weather recording projects
  (Grab, Killick, Nel, Sumner etc)
• Mountain climatology research from 1960s onwards
  (Freiman, Grab, Nel, Tyson etc)
• Current project on historical climate change
  (last 160 years) based on archival records (Nash,
  Grab)
• Recent (2000 onwards) satellite and radar based
  climate studies (Snow distribution patterns,
  rainfall patterns etc) (Grab et al.)
• Current project on snow mapping for risk
  assessment and disaster risk reduction (Grab,
  Linde)

19
Drakensberg Maluti system

• What is required?
• High resolution / high precision palaeo-climate
  verification. Proposal to do cosmogenic dating
  and ostrachod work on recently (2007) discovered
  palaeo-lake sediments (Carr, Mills, Grab, Horne)
• Establish permanent climate observatories.

S. Grab
Constraints vandalism / theft
20
Establishing a Network of High Altitude Climate
Observatories in African Mountains - progress
thus far The Global Change Research Network
in African Mountains (GCRN-AM) was launched in
July 2007, Kampala, Uganda MRI, Global
Mountain Program, African Highland Initiative et
al. Established working groups Climate
change Land use / land cover change Livelihood
s / decision making biological systems
21
Establishing a Network of High Altitude Climate
Observatories in African Mountains - progress
thus far Planning workshop on establishing
high altitude observatory systems in Ethiopia,
January 2008, Addis Ababa, Ethiopia Working
group established (Grab, Zeleke et
al.) Possible observatory sites
discussed Concept proposal has been
drafted Next phase comprehensive proposal to be
written for potential funding.
22
Concluding remarks

• Geophysical research outputs and current needs
  are highly
• variable across the respective African mountain
  regions

• Emerging requirements
• To develop a database for past geophysical
  research outputs and current programmes
• To identify high priority monitoring regions
• To establish regional monitoring networks
• - Installation of standardized weather
  stations, borehole probes
• - Links with GCOS (Global Climate Observing
  System) and GTN-G (Global Terrestrial Network
  for Glaciers)

23
Thank you