Assessing moisture sources of precipitation in the Western Pamir Mountains (Tajikistan, Central Asia) using deuterium excess

Figures & data

Table 1. List of monthly integrated and event based precipitation samples and their isotope values from two stations in the Western Pamir Mountains.

Date	Latitude	Longitude	Elevation	δ^18O	δ^2H	d-excess	Rain amount
	°N	°E	m.a.s.l.	‰ VSMOW	‰ VSMOW	‰ VSMOW	mm
Monthly samples
2012-01	37.48900	71.52244	2086	−18.7	−135.6	13.6	–
2012-02	37.48900	71.52244	2086	−19.1	−141.2	11.3	–
2012-03	37.48900	71.52244	2086	−8.8	−48.0	22.2	–
2012-04	37.48900	71.52244	2086	−5.9	−38.1	9.4	–
2012-06	37.48900	71.52244	2086	−9.9	−70.3	9.0	–
2012-07	37.48900	71.52244	2086	−2.0	−7.9	−24.2	–
2012-08	37.48900	71.52244	2086	−2.8	−5.0	−27.4	–
2012-12	37.48900	71.52244	2086	−24.4	−185.1	9.9	22.2
2013-01	37.48900	71.52244	2086	−19.3	−142.1	12.6	25.0
2013-02	37.48900	71.52244	2086	−17.9	−130.3	12.7	17.0
2012-02	37.67256	71.83347	2564	−18.4	−134.3	13.2	–
2012-03	37.67256	71.83347	2564	−11.1	−72.0	16.6	–
2012-04	37.67256	71.83347	2564	−11.0	−75.2	12.9	–
2012-05	37.67256	71.83347	2564	−6.1	−38.1	10.3	–
2012-10	37.67256	71.83347	2564	−15.6	−112.4	12.0	3.1
2012-11	37.67256	71.83347	2564	−20.0	−145.0	15.0	19.6
2012-12	37.67256	71.83347	2564	−24.1	−181.0	11.7	51.5
2013-01	37.67256	71.83347	2564	−20.5	−153.2	11.1	33.2
2013-02	37.67256	71.83347	2564	−21.7	−163.6	9.6	50.6
Event samples
2013-03-08	37.48900	71.52244	2086	−12.2	−82.8	14.6	0.8
2013-03-09	37.48900	71.52244	2086	−6.8	−41.2	13.3	1.9
2013-03-11	37.48900	71.52244	2086	−16.7	−125.2	8.4	2.0
2013-03-12	37.48900	71.52244	2086	−8.5	−59.1	8.9	0.7
2013-03-13	37.48900	71.52244	2086	−11.2	−79.1	10.1	4.3
2013-03-17	37.48900	71.52244	2086	−19.3	−146.9	7.4	0.5
2013-03-18	37.48900	71.52244	2086	−8.2	−47.2	18.1	14.6
2013-03-18	37.48900	71.52244	2086	−11.3	−76.5	13.9	14.6
2013-03-19	37.48900	71.52244	2086	−5.7	−26.1	19.6	1.0
2013-03-19	37.48900	71.52244	2086	−7.2	−35.5	22.1	1.0
2013-03-20	37.48900	71.52244	2086	−7.2	−44.6	12.7	0.5
2013-03-21	37.48900	71.52244	2086	−7.6	−61.9	−1.2	0.4
2013-03-25	37.48900	71.52244	2086	−8.7	−75.2	−5.7	0.6
2013-04-07	37.48900	71.52244	2086	−2.9	0.4	23.2	0.1
2013-04-09	37.48900	71.52244	2086	−7.8	−55.8	6.6	2.2
2013-04-16	37.48900	71.52244	2086	0.6	−10.4	−15.3	0.1
2013-04-20	37.48900	71.52244	2086	−4.4	−33.5	2.0	1.8
2013-11-04	37.48900	71.52244	2086	−14.0	−99.5	12.4	0.7
2013-11-05	37.48900	71.52244	2086	−14.0	−99.6	12.8	3.5
2013-11-05	37.48900	71.52244	2086	−14.3	−109.2	5.1	3.5
2013-11-06	37.48900	71.52244	2086	−18.2	−144.2	1.6	2.1
2013-11-06	37.48900	71.52244	2086	−15.9	−121.3	5.7	2.1
2013-11-25	37.48900	71.52244	2086	−14.2	−111.9	1.6	0.1
2013-12-05	37.48900	71.52244	2086	−18.5	−142.6	5.1	0.1
2013-12-06	37.48900	71.52244	2086	−18.3	−136.1	10.3	0.1
2013-12-07	37.48900	71.52244	2086	−19.5	−148.2	8.2	0.1
2013-12-07	37.48900	71.52244	2086	−20.5	−157.2	6.9	0.1
2013-12-08	37.48900	71.52244	2086	−18.5	−141.8	6.3	0.1
2013-12-09	37.48900	71.52244	2086	−18.7	−137.3	12.0	0.1
2013-12-16	37.48900	71.52244	2086	−9.7	−68.9	8.7	0.1
2014-01-03	37.48900	71.52244	2086	−18.4	−132.9	14.3	1.1
2014-01-04	37.48900	71.52244	2086	−19.1	−141.9	11.3	0.4
2014-01-05	37.48900	71.52244	2086	−17.1	−114.6	21.9	0.6
2014-01-08	37.48900	71.52244	2086	−30.6	−242.0	3.1	1.2
2014-01-09	37.48900	71.52244	2086	−29.9	−233.2	5.8	0.9
2014-01-25	37.48900	71.52244	2086	−21.9	−169.4	5.5	1.4
2014-01-25	37.48900	71.52244	2086	−26.0	−210.6	−2.9	1.4
2014-01-26	37.48900	71.52244	2086	−23.2	−175.8	10.1	1.1
2014-01-26	37.48900	71.52244	2086	−20.9	−155.8	11.2	1.1
2014-01-28	37.48900	71.52244	2086	−17.3	−144.4	−6.0	1.7
2014-01-28	37.48900	71.52244	2086	−22.0	−167.2	9.1	1.7
2014-01-30	37.48900	71.52244	2086	−16.9	−122.6	12.5	1.1
2014-01-30	37.48900	71.52244	2086	−15.9	−127.0	−0.2	1.1
2014-01-31	37.48900	71.52244	2086	−12.1	−80.2	16.4	1.0
2014-02-05	37.48900	71.52244	2086	−25.0	−196.4	3.7	0.4
2014-02-20	37.48900	71.52244	2086	−20.4	−156.7	6.8	1.4
2014-02-25	37.48900	71.52244	2086	−13.5	−98.9	9.4	0.2
2013-05-11	37.67256	71.83347	2564	−5.4	−24.5	18.6	0.7
2013-05-13	37.67256	71.83347	2564	−4.5	−29.6	6.8	0.1
2013-05-19	37.67256	71.83347	2564	6.6	47.1	−5.9	0.5
2013-05-20	37.67256	71.83347	2564	1.2	29.7	19.9	1.8
2013-05-24	37.67256	71.83347	2564	−0.6	4.8	9.2	1.7
2014-01-04	37.67256	71.83347	2564	−19.7	−136.5	21.1	1.5
2014-01-05	37.67256	71.83347	2564	−19.0	−130.2	21.6	1.3
2014-01-09	37.67256	71.83347	2564	−30.1	−237.1	3.5	1.2
2014-01-13	37.67256	71.83347	2564	−15.1	−121.0	0.1	1.0
2014-01-23	37.67256	71.83347	2564	−18.2	−143.8	2.2	0.3
2014-01-25	37.67256	71.83347	2564	−25.7	−199.7	6.1	10.3
2014-01-26	37.67256	71.83347	2564	−21.5	−157.5	14.5	5.5
2014-01-27	37.67256	71.83347	2564	−16.1	−122.7	6.0	0.8
2014-01-28	37.67256	71.83347	2564	−22.8	−172.7	9.8	2.1
2014-01-30	37.67256	71.83347	2564	−17.3	−124.5	14.0	10.1
2014-01-31	37.67256	71.83347	2564	−12.5	−80.4	20.0	6.8
2014-02-02	37.67256	71.83347	2564	−23.2	−182.9	2.8	0.2
2014-02-04	37.67256	71.83347	2564	−23.9	−184.9	6.4	1.8
2014-02-05	37.67256	71.83347	2564	−28.0	−225.4	−1.8	5.6
2014-02-07	37.67256	71.83347	2564	−19.8	−169.0	−10.7	0.6
2014-02-14	37.67256	71.83347	2564	−14.3	−109.7	4.5	0.1
2014-02-19	37.67256	71.83347	2564	−22.0	−172.8	3.0	2.6
2014-02-20	37.67256	71.83347	2564	−20.9	−160.4	6.6	4.4
2014-02-24	37.67256	71.83347	2564	−14.7	−118.5	−0.7	0.9
2014-02-25	37.67256	71.83347	2564	−11.9	−88.3	6.7	1.1
2014-03-03	37.67256	71.83347	2564	−24.2	−187.1	6.5	0.1
2014-03-07	37.67256	71.83347	2564	−19.4	−147.4	8.2	2.7
2014-03-08	37.67256	71.83347	2564	−21.3	−163.9	6.6	9.8
2014-03-15	37.67256	71.83347	2564	−17.7	−136.3	5.5	8.1
2014-03-16	37.67256	71.83347	2564	−15.4	−118.6	4.6	2.7
2014-03-16	37.67256	71.83347	2564	−9.6	−102.7	−25.5	2.7
2014-03-17	37.67256	71.83347	2564	−11.5	−96.9	−4.8	1.4
2014-04-04	37.67256	71.83347	2564	−16.7	−129.4	4.3	3.7
2014-04-06	37.67256	71.83347	2564	−16.3	−120.1	10.0	7.2
2014-04-07	37.67256	71.83347	2564	−10.9	−84.1	3.4	0.1
2014-04-08	37.67256	71.83347	2564	−21.8	−188.5	−14.2	0.1
2014-04-11	37.67256	71.83347	2564	−11.5	−76.9	15.1	11.0
2014-04-12	37.67256	71.83347	2564	−13.3	−93.3	13.4	23.2
2014-04-17	37.67256	71.83347	2564	−15.3	−118.9	3.5	0.8
2014-04-26	37.67256	71.83347	2564	−9.4	−67.0	7.9	0.6
2014-04-29	37.67256	71.83347	2564	−3.7	−9.7	20.2	7.8
2014-04-30	37.67256	71.83347	2564	−3.1	−5.7	19.4	3.6

This data were also used by Meier et al. (2015a) and Meier et al. (2015b).

Fig. 1. Map of Global Network of Isotopes in Precipitation (GNIP) stations (larger symbols) and additional data (smaller symbols) used for calculation of regional deuterium excess averages. Grey stars show sampling sites of this study in the Western Pamir Mountains.

Fig. 2. Map of air mass trajectories leading up to rain events in the Western Pamir Mountains. Different classes of moisture origin are color-coded. Small insert displays long distance trajectories. For a detailed description of trajectory classification see text.

Fig. 3. Dual isotope plot of δ²H against δ¹⁸O (VSMOW) for monthly integrated isotope samples of the Western Pamir Mountains. Grey dotted line is the Global Meteoric Water Line (GMWL, see Eq. 1(1) $${\delta }^2\mathrm{H}=8 ·\mathrm{ }{\delta }^{18}\mathrm{O} + 10‰$$(1) ). Black solid line is the Local Meteoric Water Line (LMWL) as calculated from the samples.

Fig. 4. Monthly deuterium excess (d) values for regional classes, corresponding to stations in Figure 1. Plots are arranged in their respective geographic setting. Solid lines are precipitation amount weighted d-averages (Eq. 5(5) $${\overline{d}}_{\mathrm{p},\mathrm{m}}=\frac{\sum (d_{\mathrm{m}} · p_{\mathrm{m}})}{\sum p_{\mathrm{m}}}$$(5) ), dashed lines are non-weighted arithmetic means (Eq. 4(4) $${\overline{d}}_{\mathrm{m}}=\frac{\sum d_{\mathrm{m}}}{n}$$(4) ). The dotted line in the “Kabul and Kashmir” subplot is the non-weighted arithmetic mean of the Kashmir valley after Jeelani et al. (2017). Sample size is shown in lower left corner of each subplot.

Fig. 5. Statistics of air mass trajectories. (a) Number of trajectories per month that had the majority of their moisture uptake in the area of a certain class. (b) Monthly percentage of the total amount of specific humidity that arrived at the measurement site via the calculated trajectories.

Fig. 6. Deuterium excess of rain events at the termination of air mass trajectories. (a) Boxplot of all event samples (whiskers end at last values inside 1.5 IQR), including sample size for each box at the top axis. (b) Monthly averages for event samples of every class. For number of trajectories per plot symbol refer to Fig. 5a. Dashed line represents monthly d values of the Western Pamir class of monthly-integrated samples (see grey plot of Fig. 4), dotted line represents monthly average of all event values.

Meier, C., Knoche, M., Merz, R. and Weise, S. M. 2015a. Single or multiple source(s) of precipitation in the Western Pamirs, Tajikistan? In: EGU General Assembly 2015. (ed. EGU). EGU, Vienna.

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Jeelani, G., Deshpande, R. D., Shah, R. A. and Hassan, W. 2017. Influence of southwest monsoons in the Kashmir Valley, western Himalayas. Isot. Environ. Health Stud. 53, 400–412. doi:10.1080/10256016.2016.1273224

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