1. Black Carbon Air Pollution in Berlin
Andreas Kerschbaumer
Berlin Senate Department for Urban Development and Environment
Directorate IX, Environment Policy
BC situation: measurements
Source apportionment
Abatement strategies
introducing myself: Berlin Department of Environmental Policy
black-carbon situation in Berlin:
measurement networks
autmated measurement devices next to small samplers for black carbon and nitrogen dioxide
which are the sources of Black-carbon high concentrations at different scales: background, residential areas and traffic sites
abatement strategies of the city

2. Introduction Impact chain of air pollution
Pollution Impact
Sources
Emission
negative effect on …
Black Carbon
traffic
hydrocarbons
Ammonia
SO2
NOx
Particles
Crops
Materials
Ecosystems
Climate
Health
other particles
house heating
Nitrogendioxide
power plants
Acidification
Industry & business
introduction to impact chain of air pollution with special attention to particles and black carbon
important to identify the sources of air pollution emissions
to consider the air pollution impact of these emissions, as the contribute in varying percentages to ambient air pollution concentrations, to acidification and eutrophication of soils and water, depending on release height and on other dispersion factors and depending on deposition issuses.
and to consider the effects on different systems like health, climate, ecosystems, materials, corps and others
Eutrophication
agriculture
Tropospheric ozone

3. Introduction Impact chain of air pollution
Links relevant for particulate matter - BC
Pollution Impact
Sources
Emission
negative effect on …
Black Carbon
traffic
hydrocarbons
Ammonia
SO2
NOx
Particles
Crops
Materials
Ecosystems
Climate
Health
other particles
house heating
Nitrogendioxide
power plants
Acidification
Industry & business
I would like to consider only the pollution impact from black carbon and from other particles on human health and on climate stemming, the first from particle emissions and the second also from urban generated NOx, which mainly comes from urban sources as traffic and house-heating, but also from power plants and other sources, depending mainly on the scale of impact considered.
Eutrophierung
agriculture
Tropospheric ozone

4. Outline EC – OC measurements in Berlin Source apportionment
automated
thermal analysis (daily means)
PM10, PM2.5, PM1
RUBIS (small devices)
thermal analysis (bi-weekly means)
PM10
high temporal (automated) and spatial (RUBIS) coverage
Source apportionment
EC and OC concentrations during high PM episodes
EC (or TC) local street contribution
Abatement measures
low emission zone (LEZ)
wood burning in small combustion plants
off-road machinery / construction sites
The outline of this talk is the following:
a short overview of Berlin Elemental – organic Carbon measurements network, consisting of a
automated filter based low volume sampler devices, where particles are collected and than further analysed in the laboratory for the main constituents as also EC and OC by thermal analysis on three different PM sizes: 10µm, 2.5 µm and 1 µm;
small sampler impactors on PM10-filters collected and analysed every 2 weeks
=> obtaining therefore a high temporal as well as high spatial coverage of the EC-OC situation in Berlin
source apportionment technique used in Berlin to quantify the contribution of single sources to EC-OC (and PM) concentrations
analysing the situation during different PM episodes
and by means of models depending on the scales considered, as chemistry-transport-models at the regional scale and street canyon models an the urban Hot-spot-scale
and I would like to present some abatement strategies which have already been realised and which are going to be introduced in the city of Berlin as
the Low Emission zone concerning vehicles access to the inner part of Berlin which have to comply with particle emission standards,
wood burning in small combustion plants mainly in private households
and off-road-machinery on public construction sites

5. Air Quality Measurements
16 automated measurements
6 at street level
6 urban background
4 semi-rural urban areas
30 Mini-Samplers at streets
higher spatial resolution
2-weekly sample periods on filters
Elemental and Organic Carbon
Passive Samplers for NO2 and NOx
Berlin EC-OC measurement networks consists mainly of two distinct types of devices:
16 automated measurement units located at different environments
6 at street level
6 at urban background levels i.e. in residential neighbourhoods
and 4 at semi-rural urban areas mainly at the edges of the city in uninhabited areas
these devices measure a variety of different ambient air pollutants, inter alia (amongst others) also particulate matter with different techniques. One of these techniques consists of collecting particles on filter material in low volume samplers considering different size fractions: 10 µm, 2.5 µm and 1 µm. Not all measurement units measure all pollutants and not all particles measurements are then also used for further chemical and physical analyses.
and 30 small filter units collecting particles on PM10-filters with an exposure time of 2 weeks obtaining therefore a higher spatial resolution but with a lower temporal resolution
the filters are then used for thermal analysis in order to determine the EC-OC-content of the air.
next to these devices there are also NO2 and NOx passive samplers.

6. AQ monitoring in Berlin Focus on hot spots & urban exposure & source analysis
Spatial distribution of Berlin Measurements:
EC OC is analysed at all Black Car symbols indicating the RUBIS network collecting the PM10-filters every two weeks and analysing thermally the EC-OC-content
on a street canyon site MC174 and in a residential neighbourhood (MC042) on PM10-, PM2.5 and PM1-Filters collected daily but analysed for EC and OC only every third day
greenish area in the centre represents the LEZ-Berlin. We have measurements inside and outside this zone. This is important to evaluate measures concerning this LEZ. Also for that a high spatial resolution in EC-OC-measurements is required, although the temporal resolution is less.
Low emission zone
Automatic monitoring site in residential areas and at the cities’ periphery
Automatic monitoring site in busy roads at the kerbside
monitoring site with miniaturised sampling devices
passive samplers for NO2
active PM10 mini samplers for EC/OC analysis

7. PM2.5 at kerbside
Aerosol composition during episodes with high (>25µg/m³), medium (15<x<25µg/m³) and low (<15µg/m³) PM2.5 concentrations over the last years from 2006 to 2011 show a coherent picture with higher percentages of inorganic aerosols during high pollution episodes and higher EC and OC fractions during low pollution episodes. This is a strong indication, that high aerosol pollution in Berlin is dominated by long range transport and by longer residential times of the aerosols in the air.
Nevertheless,
EC + OC content during high PM2.5-episodes range between 14 and 20 µg/m³ at a Berlin kerbside site.
EC percentages remain relatively constant, while OC percentages diminish from low PM burden towards high PM burden
local measures for reducing EC + OC are necessary and feasible at urban level

8. Trend EC+OC in Berlin
Berlin Total Carbon concentrations in ambient air does not show a net decrease over the last years.
Considering 2007 as a starting point (100 %), there was a slight decrease in 2009 and 2010, but in 2011 there was almost the same TC content in the air as in 2007.
If we take the street increment, that is the difference between TC measured at street sites minus TC measured a residential sites in Berlin, the picture is somewhat different:
the street level TC decreased monotonically during the last years.
2007, there was a street increment of TC of approximately 5 µg/m³ with respect to the residential situation, while this street increment decreased to levels around 2 µg/m³ in 2011.

9. Source analysis schematic of PM - TC distribution
hot spot increment
total urban contribution relevant for AQ LV compliance
urban increment
This incremental approach is based on the following consideration:
Source analysis based only on observations is done be considering measurements representative for their measurement environment.
Measurement sites outside Berlin in rural environment represent the regional background,
while sites at the city edges in uninhabited areas represent the rural influence on the city or vice-versa, depending on the wind direction,
measurement sites in residential areas represent the urban increment with respect to the rural situation, and
measurement sites in street canyons represent the street increment with respect to the urban situation.

10. Composition of PM2.5-Contributions
Source analysis Berlin origin of kerbside PM2.5
simplified receptor modelling
speciation
source contribution
Composition of PM2.5-Contributions
local traffic
urban background
regional background
local traffic
regional background
background
Combining source analysis based on observations with knowledge about emission structures and indications about contributions to concentrations based on models, we apportion the emissions to regional, urban and local traffic air pollution.
background

11. homemade vehicle tailpipe contribution
Source analysis sources of kerbside PM2.5
other sources
11%
combustion in energy
and tranformation
industries 9%
resuspension +
abrasion by traffic 4%
road transport 7% 2%
combustion in
manufacturing
industry
solvent and other
product use 5%
production processes 8%
non-industrial
combustion
10%
agriculture
waste treatment and
disposal 0% 1%
12% 3%
other mobile sources
and machinery
additional combustion
combustion in manufacturing
urban
large -
scale
local
traffic
homemade vehicle tailpipe contribution
This was done for example for the year 2007 by M. Pesch from Technical University of Berlin for the annual mean PM2.5 pollution in streets. Based on this source apportionment, road transport on the urban scale and on the street scale contribute 28 % to PM2.5 air pollution at street level, where people live and pass their time either walking, cycling or driving. Other mobile sources like non-mobile machinery and additional combustions contribute 8 % to PM2.5 levels at streets, while the biggest part (almost 60 %) of PM2.5 pollution at street level comes from outside the city (as already seen in the PM2.5-composition analysis)
background
Berlin, 2007
Source: M. Pesch Technical University - Berlin

12. Percentage of local traffic contribution to kerbside pollution52 59 46 12 11 2 7 4 10 35 17 19 0%
20%
40%
60%
80%
100%
NO2
PM10
Total Carbon
heavy duty vehicles
light duty vehicles
coach
urban bus
passenger car
Going into the traffic sector and analysing the contribution of single vehicle types to air pollution concentrations at street level – and this has been done with the aid of street canyon models –
passenger cars contribute 52 % to NO2 and 59 % to PM10, but only 46 % to Total Carbon
considering TC at street level, 35 % of TC air pollution at kerbside come from light duty vehicles

13. LEZ impact: change of particle exhaust emissions based on fleet composition at Frankfurter Allee (new emission factor data base HBEFa 3.1)
-70%
in order to diminish Total Carbon concentrations in Berlin a Low Emission Zone has been established in 2008 with special attention to Diesel exhaust emissions – thus to Elemental Carbon and to some extent also Organic Carbon emissions.
This graph shows the estimated reduction in particle exhaust emissions from the traffic sector in Berlin.
The left-most bars indicate the Emission situation in 2007, while the blue bars indicate hypothetical trends without the introduction of the LEZ in Berlin for the years based on national sales numbers and urban trend scenarios. The red and green bars indicate the actual particle emission calculations based on actual fleet composition in the same years.
there has been a reduction of 58 % in particle exhaust emissions when comparing the business-as-usual situation 2010 with the LEZ-situation in 2010 for the whole fleet, and
70 % reduction in the light-duty-vehicle sector.
emissions extrapolated to the entire main road network based on the fleet composition at Frankfurter Allee (with DPF-retrofit, only warm emissions, no cold start impact) (preliminary results, vers. 22/3/2011)

14. Berlin LEZ – impact analysis total carbon concentration
traffic related* black¥ carbon particle concentration in Berlin
This can also be seen in the TC measurements when considering only the street increment:
This graph shows the TC annual mean situation since There has been a steady decrease in the TC street increment since Compared to the level of 2007, in 2011 there has been a net 56 % reduction in TC concentration and not only within the LEZ but also outside this zone.
This is mainly due to better technology, to diesel particle filters implemented in diesel cars by the introduction of the LEZ which has been chosen big enough to avoid that people simply use different routes to get to there destination.
to take into account meteorological situations, the street increment as the difference between urban TC concentrations and street canyon concentrations has been chosen in order to assess the effectiveness of this mitigation measure.
the red bars indicate the share of situations with low wind speeds in Berlin. As you can see, compared to 2007 there have even been more days with low wind-speeds in the years 2009 to Nevertheless, the TC concentrations decreased by this 56 %.
* local BC increment at traffic sites, adjusted to traffic volumes trend relative to 2007 before LEZ came into force
¥ elemental carbon (EC) particles plus other deposited organic compounds (OC)

15. Modernisation of public bus fleet
Objectives
all busses with filter
600 busses With Euro5/EEV
Realisation
94 % busses with filter
520 busses with Euro5/EEV
Impact on Emission
37 t/ less exhaust particles
732 t/a less NOx
In order to consolidate and improve this trend, we envisage to implement all urban busses with diesel particle filters.
Compared to the situation in 2004 there has already been a 90 % improvement of exhaust particle emissions from public busses. The new measure would lead to another 37 tons less exhaust particles from public transport busses.

16. small combustion growing relevance
biomass fuel use has become more attractive
rising oil & gas prices
promoted as a renewable fuel as climate protection measure
projections suggest % growth in biomass burning
problem for PM and BC (TC) pollution?
initially focused in Scandinavia and Alpine region
abandoned in the major cites of NW Europe
Berlin: <2% of homes still heated with solid fuel
small source in urban emission inventories
average contribution 1-2 µg/m³ PM10 in Berlin/Paris/London
much higher during stagnant winter episodes (>10 µg/m³ PM10)
wood combustion in urban areas used as a secondary heating
indication that old combustion units are still used
As we have seen other sources like wood burning in small combustion devices in private households become more important, even more when diesel exhaust particles have already be minimized.
biomass have become more attractive
problem for PM and BC pollution?
focus in Scandinavia and Alpine regions (Switzerland and Austria)
majority of big western European cities believed to may abandon this issue as coal heating has become very low
solid fuel heating is a very small source in emission inventories and on an annual average this source only contributes 1-2 µg/m³ PM10
BUT, during stagnant late autumn, winter and early spring situations, this contribution can be as large as 10 µg/m³ PM10
AND there is an noticeable increase in the use of wood combustion in urban areas as a secondary heating
AND there is still a wide use of old combustion units (=>the increase of the use of wood burning is not only related to new burner technologies)
source: UBA Vienna, 2006)

17. source analysis Berlin contribution of biomass burning
result of speciation and PMF analysis
Wagener et al. in 2011 published a Positive Matrix Factor analysis focussing on Organic Carbon where they analysed a variety of carbonaceous species amongst others also levoglucosan as an indicator for biomass burning in the city of Berlin. They found out that biomass burning also at traffic sites constitutes an important source for PM – OC, especially during late autumn and early spring when biomass burning becomes the most important contribution to OC, on the same range as combustion fossil fuels.
Source: Wagener et al. (EAC 2011)

18. Small combustion Regulation in Aachen – Option for Berlin
applies to single room heaters with 4-15 kW
requires already now stricter standards for new equipment
40 mg/m³ for new devices
existing units need to comply already by 2015
75 mg/m³ for existing units
no extra transition periods granted
requires filter technology for retrofit & sufficient market coverage
initial problems for the regulator:
missing framework for monitoring and control of in use filter efficiency
project with real-world tests of retrofitted filters
lacking market for type-approved retrofit kits
lacking demand for market development
similarity with road vehicle DPF retrofit development
retrofit costs relatively high compared to value of heating devices
Thus, the city of Berlin is going to introduce a new abatement measure with regard to small combustion units.
based on the knowledge, that emission control technology exists especially for new devices exists,
but there is still a limited number of filter systems available on the market
and knowing that without setting mandatory standards there will be only little progress,
the measure comprises initial funding to boost demand and development of efficient solutions for the real world.
We also know that type-approval normally is done under very favourable conditions (that means that there is a lack of test under poor combustion – or real world – conditions
That also means that there is still a lacking information on the real – world efficiency of filter devices and on the durability.
Berlin therefore envisages next to a European framework for type approval and eventually next to a common European emission standard own emission standards for new small combustion units and also new emission standards for existing combustion units.

19. Particle filters for construction machinery
Problem:
ca. 140 t/a Diesel exhaust particles from construction machines
comparison: Diesel exhaust particles from road traffic:
2009: ca. 224 t/a (LEZ)
2015: ca. 124 t/a (LEZ without exemption)
Goal:
Reduction of Diesel exhaust emissions: 75% until 2015
i.e. 100 t/a less
Obstacle:
Filter-Regeneration at different operating conditions
Costs
Filter availability
The last reduction measure concerning Black carbon I would like to shortly introduce is regulating non-road mobile machinery. Here again special focus will be put on the exhaust particle emissions.
The problem in Berlin is, that
around 140 tons per year Diesel exhaust particles stem from construction machines
compared to Diesel exhaust particles from the road traffic, this is in the same order of magnitude and with the complete realisation of all measures due to the Low Emission Zone, in 2015 Non-road mobile machinery Diesel exhaust particle emissions will be larger than the whole Berlin on-road traffic related Diesel particles.
So, the goal is to reduce this category by approximately 75 %, that is by 100 tons per year.
Obstacles we know that exists are
the filter-regeneration at different operating conditions, or the efficiency of particle filters for mobile machineries
the costs
and also the filter availability.

20. Particle Limit Values for NRMM compared to heavy-duty vehicles
Limit values for new registration
stage IIIA
stage II and IIIA
stage II and IIIA
stage II and IIIA
Nevertheless, there is already a legal framework for NEW non-road mobile machineries concerning mainly engines with a power between 37 and 560 kW. This emission ceilings become legal manly in this year. Smaller mobile machineries with a power less than 37 kW have a much lower emission standard. Also, machines bought before 2010 normally are in use for long periods as the costs of these machines are quite elevated. And compared to particle emission levels for heave-duty vehicles these limit values for non-road mobile machinery until 2010 were much higher.
stage IIIB

21. Emission standards for machinery operating for public construction sites in Berlin
Diesel machinery:
from 2014: particle limit value stage IIIB (0,025 g/kWh), e.g. Filter retrofitting for engines ≥ 37 kW
from 2014: particle limit value stage IIIA for engines from 19 to 37 kW
Ignited machinery:
engines < 19 kW emission standards stage II according to directive 97/68/EG , also two-stroke engines
other two-stroke engines banned
Thus, this Berlin measure to reduce particle emissions from mobile machineries will focus initially on all mobile Diesel machineries operating on public construction sites making mandatory
particle limit values of g/kWh, which can be reached for example by the installation of filters for engines from 2014
and for extraneous ignition machineries, also 2-stroke engines, they must comply with stage II according to directive 97/68/EG
and other 2-stroke engines are banned from public construction sites in Berlin.

22. Thank you !
With all these measures Berlin population finally may choose whether they may breathe clean ambient are at all open urban environments or inhale their own air at their private homes.
Thank you for your attention.