chemical composition of fresh snow in himalayas and karakorum s. polesello, m. comi, a. marinoni, m....
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CHEMICAL COMPOSITION OF FRESH SNOW CHEMICAL COMPOSITION OF FRESH SNOW IN HIMALAYAS AND KARAKORUMIN HIMALAYAS AND KARAKORUM
S. PoleselloS. Polesello, M. Comi, A. Marinoni, M. Pecci, , M. Comi, A. Marinoni, M. Pecci,
G. Tartari,G. Tartari, S. Valsecchi and S. Valsecchi and E. Vuillermoz
“That pure congealed white, high Taurus snow, fanne’d with the eastern wind,...”
Shakespeare, A Midsummer Night Dream
Why should we study fresh snow?Why should we study fresh snow?
To characterise atmospheric depositions and estimate chemical loads in high altitude areas
To understand the sources of contaminants on local and regional scale
To give information on atmospheric pollution (can it act as “passive sampler”?)
To interpret glaciochemical records in ice core
Scientific development of snow studies in Scientific development of snow studies in Central Asia high altitude sitesCentral Asia high altitude sites
’’80 – Characterisation of the spatial and 80 – Characterisation of the spatial and temporal distribution of snow chemistry in temporal distribution of snow chemistry in Central Asia Central Asia
’’90 – how far does snow chemistry represent 90 – how far does snow chemistry represent atmospheric chemistry?atmospheric chemistry?
Last decade – Ice coring for past atmosphere Last decade – Ice coring for past atmosphere reconstructionreconstruction
CHARACTERIZATION OF MONSOONIC DEPOSITION AT PYRAMID SITE
1990-1992, summer – Intensive sampling of wet and dry deposition [Valsecchi et al., Sci. Total Environ., 226 (1999)
187]
1998, September – Extensive fresh snow sampling in Khumbu valley [Marinoni et al. Atmos. Environ., 35 (2001)
3183]
SAMPLING OF SNOW DURING CLIMBING EXPEDITIONS
1992, September – EVEREST (Southern slope) [Valsecchi et. al., 1999]
1998, May – ISLAND PEAK (Southern slope) [Marinoni et al. 2001]
2000, September – CHO OYU (Northern slope) [Balerna et al. Atmos. Environ., 37 (2003)
1573]
2000, October – PUMORI (Southern slope) [unpublished results]
2004: K2-2004 50 YEARS LATER PROJECT 04: K2-2004 50 YEARS LATER PROJECT [unpublished results]
April-May – EVEREST (Northern slope) June-July – K2 (Southern slope) June-July – K2 (Northern slope)
2005, May – ANNAPURNA [work in progress]
Activities of Water Research Institute (IRSA-CNR)
INDIA
C H I N A
P A K
I S T
A N
NE P A L
EVERESTEVEREST
K2K2
Determination of ion Determination of ion composition, nutrients, light composition, nutrients, light
carboxylic acids, trace carboxylic acids, trace metals, persistent organic metals, persistent organic
pollutants, in situ pollutants, in situ radioactivity in the sub-radioactivity in the sub-
surfacial snow layersurfacial snow layer
CHO OYUCHO OYU
ANNAPURNAANNAPURNA
SAMPLINGSAMPLING
Storage in special freezer to keep the snow frozen
during the transport to Italy
Field determination of pH and conductivity
Collection of fresh snow samples at different altitudes by trained
climbers
Analytical methods
ION CHROMATOGRAPHY (with preconcentration or large volume injection):– Ionic macrocostituents: Cl-, NO3
-, SO42-, NH4
+, Na+, K+, Mg2+, Ca2+
– Carboxylic acids (oxalate, acetate, formate, metansulphonate, etc..)
SPECTROPHOTOMETRY:– Nutrients: Total Nitrogen (TN), Total Phosphorus (TP)
pH
Conductivity
Ev-K2-CNR PYRAMID
Snow sampling in Khumbu valley
PUMORI
EVEREST
ISLAND PEAK
Characterization of air mass sources in Khumbu Characterization of air mass sources in Khumbu valley by Principal Component Analysisvalley by Principal Component Analysis
Factor Score
D
CEZ
GH
MR
NP
OQ
LI2 I3 I1
B
F
I
A
F1
F2
B
Factor Loading
NO3 SO4Ca
NH4
Mg
KClNa
-0,500
0,000
0,500
1,000
1,500
-0,500 0,000 0,500 1,000
F1
F2
A
2° Component:
Marine source
1° Component:
Continental source
Monsoon samples
Extra-monsoon samples
0
1
2
3
4
5
6
7
8
9
10
NO3 SO4- NH4+
Antartic Region
Himalayas monsoon season
Himalayas extra-monsoonseasonAlps
COMPARISON BETWEEN MEAN VALUES OF EVEREST REGION, DURING MONSOON AND EXTRA-MONSOON SEASON,
ALPS AND INTERNAL ANTARTICA
Data sources: Alps: Nikus et al., 1997; our unpublished resultsHimalaya : Marinoni et al., 2001; Balerna et al., 2003; Kang et al., 2004
Antartic Region: Whitlow et al., 1992; Legrand,1987.
µeq
/L
CHEMICAL COMPOSITION OF FRESH SNOW SAMPLES FROM NORTHERN AND SOUTHERN SLOPES OF
HIMALAYA DURING SUMMER MONSOON SEASON
0,00
0,50
1,00
1,50
2,00
2,50
3,00
3,50
4,00
Cl- NO3 SO4- Na+ NH4 K+ Mg++ Ca++
µeq
/l
Himalay an Northern Slope
Himalay an Southern Slope
Data sources: Valsecchi et al., 1999; Shresta et al., 1997; Marinoni et al., 2001; Balerna et al., 2003
CHEMICAL COMPOSITION OF FRESH SNOW SAMPLES FROM NORTHERN AND SOUTHERN SLOPES OF HIMALAYA DURING EXTRAMONSOON SEASON
0,00
5,00
10,00
15,00
20,00
25,00
30,00
Cl- NO3 SO4- Na+ NH4 K+ Mg++ Ca++
µeq/l
Himalay an Northern Slope
Himalay an Southern Slope
Data sources: Jenkins et al., 1983; Marinoni et al., 2001; Balerna et al., 2003
0
5
10
15
20
25
30
Cl- NO3 SO4- Na+ Mg++ Ca++
Everest 2004 (Northern Slope)
Everest region (Northern Slope)
Everest region- Khumbu (Southern Slope)
COMPARISON BETWEEN EVEREST 2004 CAMPAIGN AND PREVIOUS CAMPAIGNS IN THE SAME AREA
DURING EXTRA-MONSOON SEASON
Data sources: Jenkins et al., 1983; Marinoni et al., 2001; Balerna et al., 2003
µeq
/L
0
5
10
15
20
25
30
Cl- NO3- SO42- C2O42- Na+ NH4+ K+ Mg2+ Ca2+
K2 SOUTHERN SLOPE
K2 NORTHERN SLOPE
K2-2004 50 YEARS LATER PROJECT:K2-2004 50 YEARS LATER PROJECT:
K2 RESULTSRESULTS
µeq
/L
43
Sampling during climbing expeditionsSampling during climbing expeditions
Concentrations vs Altitude:Concentrations vs Altitude:
Is there a relationship?Is there a relationship?
0
2
4
6
8
10
12
14
16
18
µg/l
4950 5225 6500 5000 6100 6470 6460 6489 6700 7000 7300
Altitude (m a.s.l.)
K2 North SideK2 South SideEverest North Side
TOTAL PHOSPHORUS (TP)
K2-2004 50 YEARS LATER PROJECT:K2-2004 50 YEARS LATER PROJECT:
RESULTSRESULTS
PUMORI 11-17 October 2000:7 sites from 5800 to 7160 m a.s.l.
PUMORI: Concentration vs altitude
0,002,004,006,008,00
10,0012,00
5500 6000 6500 7000 7500m a.s.l.
µeq/
L
Cl
SO4
Cl NO3 SO4 C2O4 Na NH4 K Mg Ca Altitude
Cl 1,00
NO3 0,95 1,00
SO4 0,99 0,97 1,00
C2O4 -0,09 -0,22 -0,12 1,00
Na 0,96 0,84 0,94 0,09 1,00
NH4 0,95 0,94 0,95 0,05 0,93 1,00
K 0,98 0,96 0,96 -0,07 0,92 0,96 1,00
Mg 0,99 0,95 0,98 -0,08 0,95 0,96 0,99 1,00
Ca 0,96 0,98 0,95 -0,19 0,86 0,95 0,98 0,97 1,00
Altitude 0,11 0,01 0,16 -0,01 0,21 0,03 -0,06 0,01 -0,09 1,00
Correlation matrix
EVEREST 27 April- 18 May 2004:6 sites from 5200 to 7300 m a.s.l.
Correlation matrix
EVEREST: Concentration vs Altitude
0
5
10
15
5000 5500 6000 6500 7000 7500
m a.s.l.
ueq
/l
Cl
SO4
Cl NO3 SO4 C2O4 Na NH4 K Mg Ca AltitudeCl 1,00
NO3 0,56 1,00SO4 0,58 0,55 1,00
C2O4 0,13 -0,30 0,22 1,00Na 0,97 0,46 0,68 0,28 1,00
NH4 0,53 0,37 0,61 0,74 0,60 1,00K 0,79 0,36 0,36 -0,35 0,74 -0,09 1,00
Mg 0,61 0,60 1,00 0,21 0,70 0,65 0,36 1,00Ca 0,55 0,68 0,92 -0,17 0,59 0,37 0,49 0,92 1,00
Altitude 0,72 0,31 0,42 0,02 0,73 0,10 0,79 0,40 0,34 1,00
?
oxalate vs NH4 (Everest Nord)
0,00
2,00
4,00
6,00
8,00
10,00
12,00
0,05 0,15 0,25 0,35 0,45 0,55
oxalate
NH
4
Carboxylic acidsCarboxylic acids
Organic acids
0,0
100,0
200,0
300,0
400,0
500,0
600,0
700,0
UrumqiGlacier
(Tian-Shan)
RongbukGlacier
(Everest-Nord)
Pumori Sud K2 Sud K2 Nord EverestNord
Ace
tate
-Fo
rmat
e n
g/g
0,0
5,0
10,0
15,0
20,0
25,0
Oxa
late
ng
/g
Acetate
Formate
Oxalate
Data source for ice cores: Lee et al., 2002; Lee et al., 2001; Kang et al., 2001
Samples can be classified in two main classes: summer Samples can be classified in two main classes: summer monsoon and extra-monsoon samplesmonsoon and extra-monsoon samples
In the Everest region, concentrations on both slopes In the Everest region, concentrations on both slopes (Northern and Southern) are very similar in both periods(Northern and Southern) are very similar in both periods
Monsoon depositions in central Himalayas are not Monsoon depositions in central Himalayas are not substantially influenced by anthropogenic inputs (NO3 substantially influenced by anthropogenic inputs (NO3 ~~ 0.1-2.0 µeq/l ; SO4 0.1-2.0 µeq/l ; SO4 ~~ 0.05-2.0 µeq/l) 0.05-2.0 µeq/l)
In extra-monsoon period high concentrations of crustal In extra-monsoon period high concentrations of crustal ions, sulphate and nitrate are measuredions, sulphate and nitrate are measured
The concentration alternances is confirmed in ice core The concentration alternances is confirmed in ice core records and can be used for datingrecords and can be used for dating
MAIN FEATURES OF HIMALAYAN MAIN FEATURES OF HIMALAYAN FRESH SNOW CHEMICAL FRESH SNOW CHEMICAL
COMPOSITIONCOMPOSITION
Open issues:Open issues:
Source of sulphate particularly in extra-monsoon Source of sulphate particularly in extra-monsoon periodperiodOrigin of crustal particles in extra-monsoon Origin of crustal particles in extra-monsoon period (Central Asia dust storm or westernly period (Central Asia dust storm or westernly driven Saharian air masses?) driven Saharian air masses?) Formation mechanisms and sources of organic Formation mechanisms and sources of organic acidsacidsRelantionship between snow chemistry and Relantionship between snow chemistry and aerosol chemistryaerosol chemistry
FUTURE AIMS
Integration of deposition chemistry with aerosol chemistry in order to obtain complementary information on atmospheric processes
involved in Atmospheric Brown Cloud
Sulphate: 32%
Organics: 26%
Thank you !
“et eunt homines admirari alta montium et ingentis fructus maris et latissimos lapsus fluminum et ocean ambitum et giros siderum, et reliquunt se ipsos”
“And men go about to wonder at the heights of the mountains, and the mighty waves of the sea, and the wide sweep of rivers, and the circuit of ocean, and the revolution of the stars, but they do not consider themselves”
Augustinus, Confessiones