REPUBLIC OF KENYA
9th Meeting of the Ozone Research Managers of the Parties to the Vienna
Convention
Geneva, Switzerland 14 to 16 May 2014
NATIONAL REPORT
By
Kenned K. Thiong’o
Kenya Meteorological Service
E-mail: kk_thiongo@yahoo.com
1. INTRODUCTION
Kenya is a signatory to the international conventions and treaties on climate change and
environmental protection. Consequently, the country is actively participating and contributing
to the success of the World Meteorological Organization (WMO) programme through the Kenya
Meteorological Service (KMS). The Service operates several air pollution observation stations
that monitor, among other pollutants, ozone at the surface, troposphere and the stratosphere.
Realizing the importance of developing countries in the tropics to play a major role in the global
initiatives to achieve a better understanding of the atmospheric changes and the effects on the
environment linked to ozone changes, Kenya initiated its active involvement in the World
Meteorological Organization (WMO) Global Ozone Observing System (GO3OS) with the
launching of its total ozone monitoring programme in 1984. The ozone monitoring programme
has since expanded to the current surface and vertical profile observations.
2. OZONE MONITORING ACTIVITIES
2.1. CURRENT STATUS
Kenya monitors ozone in four stations namely:
 Mount Kenya Global Atmosphere Watch (GAW) station
 Nairobi Regional GAW station
 Jomo Kenyatta International Airport Urban air Pollution Monitoring Station.
 Chiromo Urban air Pollution Monitoring Station.
2.1.1. Mount Kenya GAW station
Mount Kenya Global Atmosphere Watch station (MKN) is located at high altitude (3678m a.s.l,
Longitude: 37.297o East, Latitude: 0.062o South,) in equatorial Africa. It is in a data-sparse
region of the world and provides a unique opportunity to monitor background air as well as to
conduct research in a pristine continental environment. It, therefore, samples air of the tropical
mid-troposphere as well as the atmospheric boundary layer. This is done continuously (24 hour
1
observations) in collaboration with International Twinning Partner (MeteoSwiss, Swiss Federal
Laboratory for Material Testing and Research (EMPA))
The station monitors the effect of biomass burning on the regional build- up of tropospheric
ozone, and discerning if any trends in stratospheric ozone are evident in Equatorial Africa. The
station doubles as a global monitoring and research station.
The stations is equipped with one ozone analyzer (TEI 49C). The instrument was initially
calibrated at WCC-Empa. Consistent measurements of surface ozone started in May 2002 at
MKN. Data is regularly checked for consistency with time series plots, and submitted to QA/SAC
Switzerland. QA/SAC continues to work with the station operators to transfer the responsibility
of data evaluation to Kenya Meteorological Service (KMS) staff. Ozone data is submitted to the
World Data Centre for Surface Ozone (WDCGG) in Japan Meteorological Agency (JMA).
2.1.2. Nairobi Regional GAW station
It is located close to the equator (Altitude: 1795m asl, Latitude: 1.30 S, Longitude: 36.75 E) in
Eastern Africa, and corresponds to a unique site location for the detection of ozone in tropical
region.
Nairobi regional GAW station monitors the total column of ozone using Dobson
spectrophotometer number 18 since 2005. However, these measurements commenced at the
University of Nairobi in 1984 until 2005 when the instrument was transferred to Kenya
Meteorological Service.
The station also monitors the vertical profile of ozone since 1996. It uses a Lightweight, balloonborne instrument mated to a conventional meteorological radiosonde.
It has an
electrochemical concentration cell (ECC) that senses ozone as it reacts with a dilute solution of
potassium iodide to produce a weak electrical current proportional to the ozone concentration
of the sampled air. During its ascent through the atmosphere, the ozonesonde transmits ozone
and standard meteorological quantities to the ground receiving station. These measurements
are performed ones per week.
The station commenced monitoring of surface ozone in July 2012. These observations are made
every five seconds using Thermal Scientific Model 49i.
2.1.3. Jomo Kenyatta International Airport Urban air Pollution Monitoring Station.
Air quality monitoring in most developing countries is not routinely conducted, and in some
urban areas such information does not even exist, though signs of deteriorating air quality and
health problems related to air pollution are visible.
In bridging this gap, Kenya installed an Urban Pollution Monitoring Station (UPMS) at the Jomo
Kenyatta International Airport (JKIA). The UPMS monitors Ozone (O3), Carbon monoxide (CO), Sulfur
dioxide (SO2) and aerosols or particulate matter (PM10). This installation was in line with a
2
feasibility that identified a suitable site downwind of run way 06 (RWYO6). The station commenced
its operation in July 2012.
2.1.4. Chiromo Urban air Pollution Monitoring Station
The Urban air Pollution Monitoring Station was established at the University of Nairobi in 2009
by Kenya Meteorological Service. It measures surface ozone using TEI 49C instrument.
2.2. PLANNED OZONE MONITORING ACTIVITIES
Kenya plans to implement the National Flagship Programmes under Kenya’s Vision 2030 which
include establishment of climate monitoring stations for air pollution monitoring and climate
change detection. Indeed, two stations have been established at the University of Nairobi and
Jomo Kenyatta International Airport that measures surface ozone among other pollutants. Kenya
Meteorological Service plans to establish new station across the country that will monitor both
the profile and total ozone. However, establishment of new stations may take long time to
realize due to financial limitation. There is therefore need to secure financial support from the
relevant institutions.
3. RESEARCH ON OZONE
3.1 EXISTING RESEARCH
Kenya currently does not have any major ozone research project in progress. However, several
researches on ozone are being conducted by University students at both under graduate and
post graduate level and private researchers.
Figure 1 below shows annual total column of ozone at Nairobi regional GAW station situated at
an altitude of 1795m asl (Latitude: 1.30 S, Longitude: 36.75 E). Preliminary investigations
indicate a decreasing trend of ozone from 1996 to 2013. However, further investigation is
recommended to confirm this trend since the instrument (Dobson Spectrophotometer No. 18)
was relocated from University of Nairobi to Kenya Meteorological Headquarters in year 2005.
The annual mean and standard deviation are 256.2 DU and 6.9 respectively.
3
Annual Total Column Ozone
Ozone Amount (Dobson Units)
275
270
265
260
255
250
245
1996 1997 1998 1999 2000 2005 2006 2007 2008 2009 2010 2011 2012 2013
Ozone
Time (Years)
Linear (Ozone)
Fig: 1. Annual total column of ozone in Nairobi, Kenya
The mean monthly total column of ozone is indicated in figure 2 below. The figure shows a
seasonal variation of ozone. There is a slight peak during the long rains in March-May and a
major peak in August-October just before the commencement of the short rains. Minimum
values are realized in December-February with corresponding maximum values in AugustOctober. The difference in ozone amount is attributed with stratospheric ozone fluctuations
due to the variation of the height of the tropopause (Muthama, 1989). The mean monthly
standard deviation is 5.9.
Ozone amount (Dobson units)
Monthly Total Column 0zone
265.0
263.0
261.0
259.0
257.0
255.0
253.0
251.0
249.0
247.0
245.0
JAN
FEB
MAR
APR
MAY
JUN
JUL
Time (Months)
Fig: 2. Mean monthly total column of ozone
4
AUG
SEP
OCT
NOV
DEC
0zone
Statistical analysis of ozone profiles over Nairobi split into 3 layers reveals strong yearly
variation in the free troposphere and the tropopause region, while ozone in the stratosphere
appears to be relatively constant throughout the year. Total ozone measurements by Dobson
instrument confirm maximum total ozone content during the short-rains season and a
minimum in the warm-dry season (Ayoma et al, 2002).
Seasonally Averaged Ozone Profile Nairobi (Kenya)
35
30
Layer # 3
Altitude [Km]
25
Long Rains Season
Short Rains Season
Warm Dry Season
Cold Dry Season
20
Layer # 2
15
10
Layer # 1
5
0
0
20
40
60
80
100
120
140
160
Ozone [nb]
Fig: 3. Mean “Seasonally averaged” ozone profile over Nairobi based on 8 years of ozone
sounding, for respectively long-rains, short-rains, warm-dry and cold-dry season.
As a first output of this analysis indicate that the relative ozone variability in the “stratosphere”
is weak, thus indicative of small changes in the ozone concentration in the stratosphere over
Nairobi during the last 8 years. On the contrary in the “free troposphere” and “tropopause”
regions observation showed significant changes: up to 40% of peak to peak variation with a
well-defined yearly cycle. This tropospheric ozone variability is higher than expected and may
partially be attributed to turbulent air motions (Ilyas, 1991).
Since Mount Kenya GAW station is at high attitude (3678m a.s.l), the site experiences thermally
induced wind systems that disturb free tropospheric conditions. A study to investigate the
suitability of the station showed that throughout the whole year the station is influenced by
thermally induced wind systems and the atmospheric boundary layer (Henne et al. 2008).
Ozone showed a weaker annual cycle with a minimum in November and a broad summer
maximum. Inter-annual variations were explained with differences in southern African biomass
burning and transport towards MKN. Although biomass burning had little direct influence on
5
the measurements at MKN it introduces inter-annual variability in the background
concentrations of the southern hemisphere that subsequently reaches Kenya.
3.2 PLANNED RESEARCH ON OZONE
Preliminary analysis indicates that total column of ozone in Kenya has been decreasing as
indicted in figure 1. Further analysis is urgently necessary to confirm this negative trend.
However, there is no major ozone research project to determine the status of ozone level in
country. This is occasioned by lack of a center for research on ozone-climate interactions due to
the huge funds for the establishment of the center.
4. IMPLEMENTATION OF 80RM RECOMMENDATIONS
4.1 RESEARCH NEEDS
Minimum implementation of the recommendations on research from 8ORM has been realized.
Awareness to conduct research on ozone has been enhanced through seminars and workshops.
This has led to publication of a few international journals.
4.1.1 Recommendations on Research Needs
The following recommendations will enhance research activities in Kenya.
 Establishment in Africa of a regional center for research on ozone-climate interactions.
 There are inadequate computing facilities especially for research that involve Global
models. Twinning with more advanced research centers should be encouraged
 Support investigations to resolve the differences between tropical total-ozone column
trend estimates, and those trends computed from satellite profiles.
 There is few ozone observing stations in the tropics especially in Equatorial Africa.
Governments in this region should be sensitized on the need to establish more ozone
monitoring stations.
 Budgetary constraints. The funds allocated for research are inadequate leading to few
being conducted. External sourcing of research fund would be highly welcomed.
4.2 SYSTEMATIC OBSERVATION
Systematic observations are critical to understanding and monitoring long-term changes in
atmospheric composition. Kenya has been monitoring both total column and vertical profile of
ozone since 1984 and 1996 respectively. Kenya has been keen in maintenance of existing
facilities and expansion of observing stations. These networks are maintained above a critical
level of data quality.
Archived data reports of ozonesondes include the simultaneous water vapour profiles
measured by meteorological radiosondes and the data is available for ozone research and
monitoring from the relevant world data center.
6
In the expansion and improvement of ground-based networks the country has established two
urban air pollution monitoring stations that monitor ozone, among other air pollutants. In year
2011, Kenya commenced measurements of methane (CH4) at Mount Kenya GAW station which
is both GHGs and ODSs. CH4 is measured by a Picarro G1301 instrument.
4.2.1 Recommendations on Systematic Observation
Recommendations that will enhance systematic observation in the country are;
 There is poor spatial distribution of ozone observing stations in the tropics especially in
Equatorial Africa. Governments in this region to be sensitized on the need to establish
more ozone monitoring stations. This would require both infrastructure and equipment
support in order to establish new stations.
 Redistribution of instruments from instrument-rich sites to those areas that are poorly
populated with instruments to be fast-tracked.
4.3 DATA ARCHIVING
The government provides funding for archiving all raw data from ozone monitoring stations.
However, effort is underway to facilitate submission of the data to the WOUDC. The ozone data
is archived in such a manner that they can be made easily accessible to scientists and the
general public within a reasonable period of time.
4.3.1 Recommendations on Data Archiving
 Participation in regular workshops that provide training on metadata collection and
processes for archiving data may support the effort to improve these activities within
the ozone and research community.
 It is acknowledged that obtaining data of high quality is costly and time-consuming but
is nonetheless an essential task and so data providers should be adequately funded and
recognized for their efforts in providing this data to global archives for the furtherance
of ozone and UV science.
4.4 CAPACITY BUILDING
The instruments used in ozone measurement require sophisticated calibration and
maintenance, much of which is unavailable in Kenya without international intervention. At
present, there are insufficient number of regional centres for research, calibration, and training
in developed and, especially, in developing countries. To fill this gap, Kenya has established a
regional and bilateral cooperation and collaboration (twinning) with Swiss Federal Laboratories
for Material Testing and Research (EMPA).
EMPA provide resources and opportunities for scientific and technical training, at and beyond
the instrument-operation level, thereby allowing instrument operators and other scientific
personnel in Kenya to use their data, other available data, and models in both regional and
international research areas. EMPA conducts a biennial system and performance audit of
surface ozone and carbon monoxide at the global GAW station, Mount Kenya.
7
The WMO-GAW Training and Education Centre (GAWTEC) established in Germany has been
successful in providing training in measurements and instrument calibration to all our staff
involved in ozone measurements.
4.4.1 Recommendations on Capacity Building
 Following the success of the 2011 Czech workshop, a second Dobson Workshop was to
be held in 2013 though it never took place. It is therefore proposed that this workshop
be held toward the end of year 2014.
 Resources for the exchange programs and visits of personnel from monitoring stations
from developed to developing countries should be increased in order to ensure
technology and knowledge transfer and sustained measurement programs.
 Balloon sonde networks provide critical high-resolution vertical profiles of ozone, water
vapour, and temperature, and therefore provide critical data for understanding the
interactions between atmospheric composition and a changing climate. It is therefore
important to develop training programs for the operators of these networks so that they
can produce high quality, uniform data across the globe.
 Establishment of regional centers for research, calibration, and validation in developing
countries to be encouraged.
5. CONCLUSION
The scientific community and in particular the Ozone Secretariat, to facilitate the investigations
to resolve the differences between tropical total-ozone column trend estimates, and those
trends computed from satellite profiles. This can be realized and especially in developing
nation, through initiation of research projects involving sub-regional researchers from several
countries. Much work needs to be carried out to understand many aspects of the ozone
evolution and change, including ozone-climate relationships, UV relationships, etc. The
international cooperation and assistance for improvement of the research level and quality are
appreciated especially for African countries.
6. REFERENCES
Ayoma, W., Gilbert , L., and Bertrand, C., : Variability in the observed vertical
Distribution of ozone over equatorial Eastern Africa: an analysis of Nairobi
Ozonesonde data 2002. (Paper not published)
Henne, S., Junkermann, W., Kariuki, J. M., Aseyo, J.and Klausen, J. :Mount Kenya global
Atmosphere watch (MKN) installation and meteorological characterization,
J. of Applied meteorology and climatology, Vol 47, 2008
8
Llyas 1991: Ozone depletion implication for the tropics. Published University of Malaysia and
UNEP, for international conference on tropical ozone change, Feb, 20-23 1990.
Muthama, N. J., 1989: Total atmospheric ozone characteristics over a tropical region. Msc.
Thesis, University of Nairobi.
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
9