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2000, October – PUMORI (Southern slope) [unpublished results]

2004: K2-2004 50 YEARS LATER PROJECT 04: K2-2004 50 YEARS LATER PROJECT [unpublished results]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