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Tropical Peruvian Glaciers in a Changing Climate: Forcing, Rates Of

Tropical Peruvian Glaciers in a Changing Climate: Forcing, Rates Of

Part 2: Understanding the impact that melting are having on water resources in the Callejon de Yan Glac Tropical Peruvian glaciers in a changing : YAN - Huaylas requires quantifying the annual impact of mass loss to the main river channel. We have l C C traced melt water hydrochemically from the small Yanamarey glacier catchment through the Querococha Q2 a 2+ 2- + + watershed and in the downstream tributaries of the Rio Santa with different degrees of glacier coverage. Q1 4 Forcing, rates of change, and impact to water supply O M Q3 S g Below Quero 2+ Bryan G. Mark (1) & Jefferey M. McKenzie (2) Rio (1) The Ohio State University, Department of Geography & Byrd Polar Research Center, Columbus, OH 43210, [email protected] 4000 5237 Santa Callejon de Huaylas Yanamarey catchment 700 a. Yanamarey 7 2+ (2) Syracuse University, Department of Earth Sciences, Syracuse, NY 13210, [email protected] Mg 2- Contour interval = 1000 m 200 0 200 400 m 600 6 SO4 3000 5000 500 5 2000 Lake Watershed 400 4 40 Glaciar Huallanca Glacierized -100 35 1100300 3 8 50'° 4000 30 4800Yanamarey 1000200 2 -250 25 5000 ° Colcas Terminus 900100 1 6259 20 99 (m) 78 00' recession

Negra Low (C) Tropical glaciers are intriguing and presently rapidly disappearing components of the cryosphere that -400 (m/yr) 15 98 1. Glacier watershed (mm) 8000 0 Paron (m) literally crown a vast ecosystem of global significance. They are highly sensitive to climate changes SANTA LOW (m/yr) 10 97 700 Llullan -550 -100 P -1 88 ° 5 over different temporal and spatial scales and are important hydrological resources in tropical 6395 Kinzl -200600 Melt -2

South America Llanganuco 77 20' -700 0 82 Qt (YAN) -300500 -3 highlands. Moreover, an accurate understanding of the dynamics and climate response of tropical 1930 1950 1970 1990 2010 73 T 2+ + + 2- - - Equator 0 6768 9 10'° glaciers in the past is a crucial source of paleoclimatic information for the validation and comparison CordilleraRanrahirca Negra 62 * -400400 -4 Ca Na +K CO +HCO Cl 5000 48 of global climate models. We have studied both present-day glacier recession and field evidence of 1939 300 b. Querococha (Above) Piper plot of major ion chemistry from the YAN-Querococha watershed. Q3 is on a mixing 4000 Q1 Buin 200 line between the glacial snout and Q1, with a relative contribution of 50% from each end member. 6125 Q2 The size of each symbol is proportional to TDS. past episodes of deglaciation in Perú to test hypotheses related to this important climatically forced 3000 Querococha watershed 100 Q3 process in the developing Andean region. Modern glacier recession raises the issues of the nature of Marcara 2 0 2 4km 0 Anta 5000 climatic forcing and the impact on surface water runoff. While rates of contemporary glacier recession Paltay 08- 06- 10- 19- 19- 28- 29- 04- 05- 23- 02- 25- Cord Blanca 0S° JANGAS Contour interval = 200 m Jun- Jul- Aug-Sep- Oct- Nov-Dec- Feb-Mar- Apr- Jun- Jun- appear to be accelerating, careful analysis of the timing and volumetric extent of deglaciation from 6162 5237 Glaciar - C Yanamarey 98 98 98 98 98 98 98 99 99 99 99 99 l a 2+ Rio Santa C Late Glacial and positions provides a historical comparison with important Quilcay 2. Downstream confluence c. Callejon de Huaylas + + Huaraz 6395 Cord Negra 2- implications for understanding glacial-to-interglacial transitions. Our research incorporates three 2.5 M Querococha 4 4800 g specific parts:(1) an analysis of the spatial variability and climatic forcing of late 20th century glacier Cordillera O 2+ Blanca YAN 5197 Olleros S recession in the Queshque massif of the southern Cordillera Blanca, Peru;(2) an evaluation of the SANTA2 5322 discharge 2.0 Chancos 8S° Olleros Llanganuco hydrological significance of glacial with respect to streamflow in the Cordillera Blanca Q3 ° 4400 1.5 Paron Q

77 00' region; and(3) an evaluation of the rate and extent of deglaciation during the late- and Cordillera Q Vilcanota Yanayacu 9 50'° 4800 2+ 2-

Lima Q2 Q1 Max 1.0 Holocene compared to modern glacier recession in the /Quelccaya. We review Mean Mg SO4 4000 our results in the context of outlining a vision for using glacial-environmental assessment as a focal Pachacoto discharge discharge 0.5 point to investigate both physical and human dimensions of . 4400 R2 =0.65 16° S 4400 >4000 m in elevation 4000 0.0 Querococha SANTA1 0204060 80° W 72° W Negra2 3980 Q3 Part 1: We use a combination of aerial photogrammetry, satellite imagery, discharge 3. Tributaries of Rio Santa Glacierized area (%) Negra1 Tuco and differential GPS mapping to quantify the volume of ice lost between AD 40 0 40 80 km (Above) Hydrological and climatological data from the successively larger CONOCOCHA catchments of the case study (see Fig. 1): (a) observational data from the Yanamarey 1962 and 1999 from 3 glaciers of different aspect. A heuristic sensitivity analysis Glacierized % (1962) (1997) glacier catchment, including monthly measurements of specific discharge (Qt) (mm) -2 Paron 55 52 from YAN plotted with the monthly precipitation totals (P) (mm) and monthly average 2+ + + 2- - - indicates the 9.3 Wm required to melt the observed ice loss can be explained 2 temperature (T) (degrees C) sampled over the 1998-99 hydrological year, plotted with -1 (Above) Case study location maps of successively larger scale: Callejon de Huaylas, a watershed of ~5000 km draining the Cordillera Blanca, Perú, to the upper Rio Santa. Llanganuco 41 36 CO +HCO Cl 2 2 Ca Na +K 3 3 by a 1K rise in temperature and 0.14 gkg increase in specific humidity. gauge and sample locations are identified; Querococha watershed, 60 km , showing the discharge and water sampling points; Yanamarey catchment, 1.3 km the glacier melt (Melt) calculated from a simplified hydrological mass balance; (b) Cedros 22 18 specific discharge data from locations in the Querococha watershed plotted with between 4600 m and 5300 m, 75% of which is covered by glacier ice. The shaded region shows the outline of Glaciar Yanamarey in 1982, with contours and a center-line to Chancos 25 22 show distance from headwall with 100 m intervals (after Hastenrath and Ames, 1995a). Terminus positions are mapped onto a common datum, based on surveys for 1939, monthly precipitation at the Querococha gauge (both in mm), on the same scale as 5680 (Above) Piper plot of major ion chemistry from the averaged end-members in the Callejon de (SPOT image 1997) 1948, 1962, 1973, 1982, 1988, 1997, 1998, and 1999. The latter three positions were mapped using differential GPS. The cumulative terminus recession from the 1939 Colcas 20 18 (a); (c) magnitude and variation of annual stream discharge with percentage of Queshque Huaylas watershed. The Rio Santa is on a mixing line between the glacierized Cordillera position is shown (m) on the inset graph as solid line, with solid rectangles for years with corresponding terminus position mapped (data from A. Ames, personal glacierized area in the Río Santa tributaries, shown by ratio of maximum monthly East (E) Olleros 12 10 Blanca tributaries and non-glacierized Cordillera Negra tributaries, with a relative contribution of Queshque communication, 1998), along with average recession rate between years with mapped termini (in meters/year). Asterix marks the location of a , where daily discharge to mean monthly discharge (max Q / mean Q); labeled data points Querococha 6 3 66% from the Cordillera Blanca. The size of each symbol is proportionate to TDS. (5680) temperature and monthly precipitation were recorded discontinuously from 1982.•1999 glacier surface from correspond to gauge locations shown on map. 5403 differential GPS survey

0 Glacial moraine chronology provides a basis for evaluating the timing and rates of deglaciation for late glacial and Holocene paleoglaciers in the 00 Part 3: 5 Peruvian . Rates of deglaciation were calculated for paleoglacier volumes on both the western side of the Quelccaya and the northwest side Mururaju Mururaju Queshque East (E) (5688) of the Cordillera Vilcanota, Perú. The late glacial episode of deglaciation on the west side of Quelccaya is coincident with rapid deglaciation in the Cordillera Queshque (S) Main 5688 Blanca of north central Perú that occurred during the interval, out of phase with glaciation in the North Atlantic region (Rodbell and Seltzer,

0 0 5 2000). The fastest rates of deglaciation were calculated for the youngest paleoglaciers, corresponding to the last few centuries. These rates fall within the 00 8 400 46 (SW) 4 Lagunas Queshque 3 range of modern rates measured on the , interpreted as evidence of enhanced atmospheric temperatures (Thompson, 2000). Applying 5000 the maximum modern deglacial rates to the late glacial ice volumes results in deglaciation over a few centuries, consistent with lake-core evidence. These

Aerial photos (left) and satellite imagery results imply that rates of deglaciation may fluctuate significantly over time, and that high rates of deglaciation may not be exclusive to the late 20th century. (above) were used to map glacier extent in 1962 and 1997. Digital glacier surfaces Queshque Main (SW) were reconstructed with photogrammetry N 300 120 L. Casercocha small small and differential GPS. Contour map (upper Upismayo Valley large large right, interval = 200m) of the glacierized 250 100 areas on the Queshque massif (photos of 3 glaciers to left). Three tones of shading W E Lake Ice1 200 80 represent: 1999 glacier areas of the Moraine Ice2 glaciers (light grey); the 1962 areas Stream Ice3 150 60 mapped from aerial photography (blue); Modern Ice 4450 ± 45 and other areas mapped from 1997 SPOT Pleistocene , S 10 imagery (dark grey). Dots represent GPS- 100 40 mapped surface elevations from 1999 Cordillera Blanca Q. Upismayo survey. Dashed lines are ridges separating 10,362 ± 73 50 20 Mururaju (S) the major drainages. Digital elevation 0 model (DEM) generated from digitized DEM (1:25,000) 1:25,000 contour lines (lower right). 0 0 L. Comercocha 2.0 20 10 H3 H2 H1 Qori Kalis glacier 265 Upismayo Valley ± ice3 ice2 ice1 (Left): Normalized anomalies 25 1962 area 2830 70 of annual precipitation totals 328 ± 46 Glacier Volume Deglacial Interval (yrs) Deglacial Volume (km3) Deglacial Rate (10-5 km3/yr) 260 ± 3 250 (mm) from 45 Peruvian 1999 area 13,380 150 (km ) (small) (large) (small) (large) (small) (large) 20 1.0 stations above 3000 m a.s.l. 1962-99 area Cordillera Vilcanota Upismayo Valley Queshque Q. Jalacocha 255 Kilometers Between 1953-1998. Vertical ice3 1.17 5150 4400 3746 12073 11605 10950 0.43 1.31 3.56 3.71 3.93 25.44 29.77 34.97 Main (SW) Lakes 200 bars extend 2 standard errors 15 Ausengate ice2 0.74 2504 2135 1823 4986 4651 4472 0.19 0.88 3.81 4.09 4.25 35.14 41.22 48.27 250 0.0 of the mean on either side of (6372 m) ice1 0.55 489 384 279 0.55 0.69 112.47 143.23 197.13 141.10 179.69 247.31 mm the annual averaged anomaly. -2 Glacier 10 245 mod 0.14 150 Huancané Valley Wm Rivers Nevado -1.0 H3 0.43 3778 2400 1511 0.09 0.57 2.38 3.75 5.96 15.09 23.75 37.72 Surface lowering (m) 5 240 Ausengate 100 Mururaju (S) Queshque Quelccaya (6372 m) H2 0.34 1806 700 617 9787 9130 8133 0.34 0.48 3.47 3.72 4.18 26.58 68.57 77.80 East (E) 235 H1 0.19 492 290 0.19 0.33 38.62 65.52 --- 67.07 113.79 --- 0 Ice Cap -2.0 2024 810Kilometers mod 0.14 240 245 250 255 260 (5645 m) 50 1950 1960 1970 1980 1990 2000 230 Huancane Solar radiation (Wm -2) Year Valley Moraine chronology in the Upismayo and Huancané valleys allows for a rates of deglaciation to be calculated using 225 paleoglacier volumes estimated from a digital elevation model (DEM). Radiocarbon ages for moraine features are shown in 0 2.0 (Left): Annual deviation of Quesh Main (SW) Quesh East (E) Mururaju (S) the site maps above (from Goodman et al., 2001). Three paleoglacier volumes were reconstructed for each valley, as 1963-1978 1978-1983 1983-1991 temperature from the DEM 1962-99 Huancané Valley shown with contour lines in figures to left (Mark et al., 2002). The estimated rates are tabulated above, and shown in bar 1961-1990 average from volume 1962-99 surface graphs, as explained below. Glacier Aspect change mean area lowering Accelerating rates of deglaciation for the Qori Kalis -5 3 -1 29 Peruvian stations 3 3 3 2 1.0 (10 m )(10m )(m) Lake 3 glacier (photo above) in 10 km yr , calculated located between 9-12 S H1 Volume (km ) of each reconstructed paleoglacier is calculated using gridded-model surfaces and the DEM. Modern glacier Queshque Main SW 48951 2197 22 -2 12,230 ± 180 1.36 from terrestrial and aerial photogrammetry N Wm Moraine volume ('mod') was estimated from surface area by the formula V=28.5 S (after Chen and Ohmura, 1990). Deglacial latitude, ranging in Queshque East E 2215 407 5 Wi nt er Sol st i ce H2 (Brecher and Thomas, 1993). elevation from 20 - 4600 m Mururaju S 5441 1079 5 6600 - 7500 Stream interval (yrs) represents the conceivable time range over which the paleoglacier deglaciated from successively less ºC 0.0 View of Ausengate and the Cordillera Vilcanota from the a.s.l. The trends are based W E 6200 - 6600 H3 extensive end moraine positions. The interval is presented as a mean surrounded by the one-sigma range in calibrated Upismayo valley (below). Landsat image draped over Modern Ice ± on ordinary least squares 5800 - 6200 270 80 radiocarbon ages. Where available radiocarbon dates include more than one constraining age for a moraine, the maximum DEM of the Vilcanota, viewed from NW (above). 3 regression, and the -2 S and minimum possible intervals are provided as 'large' and 'small' intervals respectively.Deglacial volume (km ) represents Paleoglacier Volume needed Time needed -1.0 (Above): Mean annual solar radiation flux (Wm ) 5500 - 5800 vertical bars extend 2 5100 - 5500 the volume lost from the paleoglacier in 2 possible deglacial scenarios: a 'large' volume from complete deglaciation; and a (x modeled) (yrs) standard errors of the verses average surface lowering (m) calculated for 10,910 ± 160 'small' volume considering only the volume lost between successive moraine positions.Deglacial rate (10-5 km 3 yr -1 ) is Upismayo Valley the 3 Queshque glaciers, identified by name. 4600 - 5100 H3 5-8 210-370 mean on either side of the calculated by dividing the deglacial volume by the deglacial interval, such that the 'small' rate equals 'small' volume divided H2 20-40 130-230 -2.0 annual average. 4100 - 4600 Huancané Valley by 'large' interval, and 'large' rate equals 'large' volume divided by 'small' interval. Ice3 3-5 500-630 1950 1960 1970 1980 1990 2000 3500 - 4100 Ice2 20-25 110-150 2800 - 3500 Year ± The increments in volume (multiple of the modeled volume) and deglacial interval (number of years) needed for the modeled A 30m DEM was generated from 1:25,000 and 1000 - 2800 10,870 72 paleoglaciers to equal the most recent rates of deglaciation are tabulated to right. 1:100,000 maps and used to model insolation No Data

receipt to the surface. Integrated clear-sky values -2 5600 Wm References of global radiation forwinter and summer solstices Summer So l st i c e 2670 ± 95 Acknowledgments 5500 (SW) Queshque Main (Left): Hypsometric curves for Brecher, H. and L. G. Thompson, 1993: Measurement of the retreat of Qori Kalis glacier in the tropical Andes of Peru by terrestrial photogrammetry. (right) show seasonal shading differences. A 7900 - 8700 5400 the Queshque glaciers, showing alley L. Acconcancha Photogrammetric Engineering & Remote Sensing 59(6), 1017-1022. -11° S (E) Queshque East simple transmittivity model using the DEM 7600 - 7900 L. Paco Cocha Kathy Welch, Anne Carey 5300 area with altitude. The Chen, J., and A. Ohmura, 1990: Estimation of alpine glacier water resources and their change since the 1870s. Hydrology in Mountainous Regions. I- (S) Mururaju indicates solar radiation related to altered +0.4 7400 - 7600 and Berry Lyons are Queshque Main glacier has Quelccaya Ice Cap Hydrological Measurements; the Water Cycle (Proceedings of two Lausanne Symposia, August, 1990). IAHS Publ. No. 193, 127-135. 5200 cloudiness was not a predominant climatic forcing Hancane V gratefully acknowledged for more mass exposed at lower 7100 - 7400 Hastenrath, S., Ames, A., 1995. Recession of Yanamarey Glacier in Cordillera Blanca, Peru, during the 20th century. Journal of Glaciology 41(137), 191-196. 5100 of mass loss. facilitating laboratory elevation. 6700 - 7100 9980 ± 255 Goodman, A.Y., Rodbell, D.T., Seltzer, G.O., Mark, B.G., 2001. Subdivision of glacial deposits in southeastern Peru based on pedogenic development and °C5000 per decade (R ight, top) : Mean annual clear sky solar radiation 6300 - 6700 radiometric ages. Quaternary Research 56(1), 31-50. analyses at Ohio State ElevationElevation (m) (m) 4900 flux (Wm-2) averaged over the 3 different areas for 5800 - 6300 Mark, B.G., Seltzer, G.O., Rodbell, D.T., Goodman, A.Y., 2002. Rates of deglaciation during the last glaciation and Holocene in the Cordillera Vilcanota- University. Don Siegel 4800 each of the glaciers, representing the surface 5300 - 5800 Quelccaya Ice Cap region, Southeastern Perú. Quaternary Research 57(3), 287-298. supported laboratory work at areas for both 1962 and 1999, as well as the area Syracuse University. Initial 4700 4600 - 5300 Mark, B.G., Seltzer, G.O., 2003. Tropical glacier meltwater contribution to stream discharge: a case study in the Cordillera Blanca, Peru. Journal of vacated by the ice between these dates (1962-99). field work was conducted 4600 2800 - 4600 Glaciology 49(165), 271-281. The mean annual total radiation is greatest over Mark, B.G., Seltzer, G.O., 2005. Recent glacial recession in the Cordillera Blanca, Peru (AD 1962-1999). Quaternary Science Reviews, in press. while BGM was supported 0 0.5 1 1.5 2 2.5 3 the east-facing glacier. No Data 1012345Kilometers12,240 ± 170 11,183 ± 109 on a U.S. Fulbright 2 2 60612Kilometers Rodbell, D. T. and Seltzer, G. O. (2000). Rapid Ice Margin Fluctuations during the Younger Dryas in the TropicalAndes.Quaternary Research 54 , 328-338. Glacier area (km ) ) Thompson, L. G., 2000: evidence for climate change in the Tropics: implications for our future.Quaternary Science Reviews 19 , 19-35. Scholarship, 1997-98.

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