Joe Magner, Lu Zhang, Lee Engel & *Jenny Jasperson University of Minnesota, St. Paul & *UMD

Transcription

1 Jo Magnr, Lu Zhang, L Engl & *Jnny Jasprson Univrsity of Minnsota, St. Paul & *UMD

2 Hydrogn & Oxygn Priodic Tabl Dutrium ( 2 H) accounts for approximatly % of all th naturally occurring hydrogn in th hydrosphr. Th most common isotop, hydrogn-1 or protium ( 1 H) accounts for mor than 99.98%. Z n n H H H Li B n 2 H 3 H 2 2 n 3 H 4 H 3 4 H 5 H 4 4 n 5 H 6 H 4 Li 5 B B C 7 5 Li 6 B 7 B 8 C N 8 6 Li 7 B 8 B 9 C 10 N O 9 7 Li 8 B 9 B 10 C 11 N O 12 F H 7 H 8 Li 9 B 10 B 11 C 12 N O F N H 8 H 9 Li 10 B 11 B 12 C 13 N O F 16 N Na 12 Oxygn-18 ( 18 O) accounts for 0.2 % of all th naturally occurring oxygn in th hydrosphr; whras 16 O accounts for 99.86% H 10 H 9 10 L i 11 L i 12 L i 11 B 12 B 13 B B 12 B 13 C 14 N O B 14 C 15 N O B 15 C 16 N O B 16 C 17 N O B 17 C 18 N O F 17 N 17 F 18 N 18 F 19 N 19 F 20 N 18 Na 19 Na 20 Na 21 Na Mg Mg 21 Mg 22 Mg Al A l 23 A l Si S i P 16

3 Add a proton = Havir Elmnt Wighs mor than th mor abundant 1 H and 16 O watr

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5 20.00 MN Local Mtoric Watr Lin 0.00 y = x /19/ R² = /20/12 5/24/12 4/15/ /11/11 Snow Pack δ 2 H /11/ Lak Effct Snow Pack Gulf Air Storms /20/12 Snow Pack aftr Rainfall 8/18/12 localizd prcip Jasprson, δ 18 O

6 Amity Crk : Stabl Isotops of Hydrogn and Oxygn GW_Basflow2010 SW_Basflow Snow_Spring Rain_Spring2011 SW_Spring Wll March Wll May Snow_Spring2012 Palo SW May Wll May Rain_Spring Palo SW March GW_Spring Composit Mix SW_Spring2012 Palo SW_Spring2012 Jasprson, 2013 Rain_SummrEvnt

7 Location of data is dirctly rlatd to tmp Coolr tmps lightr isotopic composition Warmr tmps ratio of havir isotops in th prcipitation incrass with incrasd air tmps. Diffrncs btwn yars basd on timing of prcipitation & wt vs dry yars Effct of lvation: Mizoram, India Vs Cntral MN Effct of sason & prcipitation: Cntral MN

8 40 Mizoram and Minnsota Zawlnuam Lak -20 AR δd y = 8x LRC MC MWL -60 Mizoram Vaphai Rain Linar (MWL) From Brooks t al δ 18 O -120

9 Sasonal Isotop Pattrn 2007 Spring Summr MWL Linar (2007) Linar (Summr) Linar (Summr) Linar (MWL) y = 8x y = x δd y = x y = x Prcipitation Timing: 2007 Vs δ 18 O

10 Mtoric Watr Lin (MWL) Rlationship btwn D and 18 O plot to th lft of th MWL. D=8* 18 O+10 MWL D Evaporation 18 O Engl, 2014

11 Hydrogn vaporats fastr thn oxygn Procss know as Fractionation Transpiration dos not crat th sam vaporativ signatur Exampls Evaporativ Lin intrsction: Rocky Mountain D = -130, 18 O = -18 Cross Rivr D = -70, 18 O = -11

12 DC Rgional Isotopic Fingrprint Dlta D Globl = 8x + 10 R² = 1 Dlta 18O Local = 8.312x R² = MWL Laura Lodg Outsp Local Brown Rocky Pishkun Linar (MWL) Linar (Local)

13 Cross Rivr Isotop Data April July Sptmbr April Prcipitation y = x y = 8x April 1855 Spring July Sumbl Crk Lak Suprior July δ D y = x y = 4.973x Lak Suprior April Lak Suprior Sptmbr Babtism Rivr April -60 Babtism Rivr July Babtism Rivr Sptmbr y = 3.827x LMWL -80 GMWL Linar (April) Linar (July) δ O 18 Zhang, Linar (Sptmbr) Linar (LMWL)

14 Lak Suprior data is narly stationary: hydraulic rsidnc tim (HRT) ~ yrs Baptism Rivr data stays nar th MWL: trrstrial landscap supplis most watr April: lightr snow influncd July: havir mga storm (clustrd) Sptmbr: both (unclustrd) with narly th sam July shift in slop & intrcpt.

15 Cross Rivr basin ovrall, has limitd watr storag basd 2012 data shifts What supports basflow? Most storag occurs in laks and wtlands not much in th trrstrial uplands Wilson Lak: 2.6 to 9 yar HRT Houghtaling wtland complx: 1 to 2.4 yar HRT

16 Dcisions about how th land is usd Issus: Vgtation, Roads, Homs (othr imprvious surfacs) and ski slops Quantity: magnitud, distribution & timing of prcip, storag (HRT) and flow Quality: flow & sdimnt rgim and how it drivs aquatic lif.

17 Usd th 24 Sntinl Laks which ar apart of th Sustaining Laks in a Changing Environmnt (SLICE) study. Sampld 3 tim pr yar from 2008 to Dsignd to captur annual variation in D and 18 O.

18 Engl, 2014

19 y = 8x D ( ) y = x R² = O ( ) 90 Barhad Echo Elphant Tait Trout Whit Iron MWL Canadian Shild Linar (MWL) Linar (Canadian Shild)

20 Lak ID Lak Basin hctars (acrs) Littoral Ara (%) Total Watrshd Ara hctars (acrs) Watrshd: Lak Max. Dpth mtrs (ft) Man Dpth mtrs (ft) Lak Volum acr ft Bar Had (659) 56 Lak bathymtry basd on original survys in ,101 (2,722) 4.1 : 1 Locatd in St. Louis County, MN within Bar Had Stat Park. Bd substrat is primarily bd rock. Larg wtland complx on southrn nd. Lak has a low sill. 14 (46) 4.2 (13.8) 9,094

21 Lak Nam Min Max Min Max Min Max Rang (Yr) Rsidnc Tim (Yr) Barhad Why did th rsidnc tim to incras in 2010?

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25 τ = ω -1 [(A/B) 2 1] 1/2 Whr: τ is th hydraulic rsidnc tim, in days, ω is th angular frquncy of variation (2π/365 days), A th prcipitation or input amplitud, in prmil valu; dfind as and B th output amplitud; ( ).

26 Av T- C Av T- C

27 Prcip- mm Prcip- mm

28 ΔO ΔO

29 Output B max B min HRT max HRT min Cross Mouth Littl Wilson Wilson Lak Cross Toohy Lak South Wigam Cross Four Mil Cr Baptism Lak Suprior Richy Lak Houghtaling

30 Snow composit may yild an avrag 18 O of 22, whras, summr rainfall could hav an avrag 18 O of 4. Isotopic rang for 18 O = 18. Howvr, bcaus mixing of nw prcipitation occurs with xisting watr hld in storag, th isotopic rang bcoms considrably smallr than 18.

31 Th rang of variation is in ffct a rflction of hydraulic rsidnc. An aquifr or larg lak that intgrats annual prcipitation ovr svral yars will hav a small rang (1-to-4 ) nar th man annual avrag for prcipitation, or 9 for this xampl. A stram or pond will likly hav a largr rang (7-to-16 ) bcaus pr-vnt storag in a stram or pond is lss than a larg lak or aquifr.

32 Whr: Pav + Si + Gi - Eav - So - Go = ΔV/Δt Pav = annual avrag prcipitation input S = sum of surfac inflows and outflows G = sum of subsurfac inflows and outflows Eav = annual avrag vaporation output ΔV/Δt = annual chang in lak stag

33 δ is th stabl isotop of 18 O assum a wll mixd lak, δ outflows ~ δ L δ E is not dirctly masurd - xprimntally drivd rprsnts th largst rror

34 Thr diffrnt nd-mmbrs dpnding on tmpratur and vaporation, Cool tmp or light ratio signatur Warm tmp or havy ratio signatur Fractionatd or vaporativ signatur Estimat Hydraulic Rsidnc Tim (HRT) with a minimum of 3 sampls/yar by sason, Estimat rlativ mixing of nd-mmbrs via strngth of nd-mmbr input.

35 Hydrology and th Managmnt of Watrshds (4th Edition)