Laboratoire Mixte Internacionale GREATICE Glaciers and Water Resources in the Tropical Andes, Climatic and Environmental Indicators

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1 Laboratoire Mixte Internacionale GREATICE Glaciers and Water Resources in the Tropical Andes, Climatic and Environmental Indicators Phase I (Results) Phase II (Perspectives) Álvaro Soruco Luzmila Dávila

2 Front Variations Climate Forcing + Glacier Dynamics Mass Balance Variations Climatic Variations Number of glaciers

3 Key indicators of CLIMATE CHANGE Mountain Glaciers Water Resources (Soruco et al, 2015) 3

4 TROPICAL GLACIERS (Kaser, 1996) Región Superficie (km²) Superficie (%) Región Superficie (km²) Superficie (%) Perú Kilimanjaro Bolivia Ruwenzori Ecuador Mt Kenya Colombia Irian Jaya Venezuela Total Total

5 1.INTRODUCTION 2. OBJECTIVES 3. STUDIED SITES 4. METHODS 5. RESULTS IN BOLIVIA 6. RESULTS IN SOUTH AMERICA 7. CONCLUSIONS AND PERSPECTIVES 5

6 ZONGO Glacier CHACALTAYA Glacier ZONGO Glacier CHACALTAYA Glacier CHARQUINI Glacier ZONGO Glacier CHARQUINI Glacier

7 The objectives of GREATICE were organized in 3 axes: Axe 1: The Glacier Evolution from the Little Ice Age (LIA) to present (people in charge: A. Rabatel y A. Soruco). GLACIOLOGICAL MASS BALANCE & glacier dynamics Axe 2: The glacier energy surface balance and climatic parameters (people in charge: J.E. Sicart y L. Maisincho). ENERGY BALANCE & MODELS Axe 3: The Impact of Glacier Decline on Water Resources (people in charge: M. Villacis y T. Condom). WATER RESOURCES & WATER MANAGEMENT

8 1.INTRODUCTION 2. OBJECTIVES 3. STUDIED SITES 4. METHODS 5. RESULTS IN BOLIVIA 6. RESULTS IN SOUTH AMERICA 7. CONCLUSIONS AND PERSPECTIVES 8

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10 1.INTRODUCTION 2. OBJECTIVES 3. STUDIED SITES 4. METHODS 5. RESULTS IN BOLIVIA 6. RESULTS IN SOUTH AMERICA 7. CONCLUSIONS AND PERSPECTIVES 10

11 MASS BALANCE: gain and loss of mass from a glacier Equilibrium Line Altitude (ELA) Gain mass βn Accumulation >0 Area Ablation Area Loss mass βn<0 11

12 GLACIOLOGICAL METHOD: estimates de mass balance in a direct way Accumulation Zone Ablation Zone Paterson, 1994

13 HYDROLOGIC METHOD: estimates de mass balance in an indirect way.

14 GEODETIC METHOD: estimates de glacier volume change. Data acquisition Ground Control Points Aerotriangulation Photogrammetric restitution DEMs interpolation x y z y z x

15 1.INTRODUCTION 2. OBJECTIVES 3. STUDIED SITES 4. METHODS 5. RESULTS IN BOLIVIA 6. RESULTS IN SOUTH AMERICA 7. CONCLUSIONS AND PERSPECTIVES 15

16 Inventory of E. Jordan (1991) 1826 glaciers (592 km²) in 1975 Zongo km 2 Chacaltaya km 2 Charquini Sur km 2 80% of the glaciers has a Surface < 0.5km 2 16

17 Lost Surfaces = 48% (34 km²) Lost Surfaces = 35% (9.5 km²)

18 CHARQUINI GLACIERS (LIA-Present)

19 EVOLUTION OF TELATA GLACIER (HOLOCENO - LIA) 57 Moraines on Telata Glacier Holocene fluctuation (11 kyr BP). Rapid decline from 10.8 kyr a 8.5 kyr. Slow and regular decline from 8.5 kyr a LIA.

20 CHACALTAYA GLACIER ( ) B. Francou B. Francou B. Francou B. Francou E. Ramirez P.Ginot

21 ZONGO GLACIER ( Present) 0.13 m.w.e/yr 0.25 m.w.e/yr m.w.e/yr m.w.e/yr m.w.e/yr

22 GEODETIC MASS BALANCE OVER 21 GLACIERS ( )

23 WATER RESSOURCES OF LA PAZ CITY

24 1.INTRODUCTION 2. OBJECTIVES 3. STUDIED SITES 4. METHODS 5. RESULTS IN BOLIVIA 6. RESULTS IN SOUTH AMERICA 7. CONCLUSIONS AND PERSPECTIVES 24

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26 GLACIER FLUCTUATIONS OVER THE HOLOCENE RITACUBA Glacier, COLOMBIA (Antarctic Cold Reversal, ~14 kyr BP) Telata Glacier, BOLIVIA Jomelli et al., Nature, 2014 Jomelli et al., Nature, 2011

27 GLACIER FLUCTUATIONS FROM LIA 10 principal moraines of LIA (liquenometry, 14C, 10Be) Rabatel et al., Quat. Res., 2008 Jomelli et al., Palaeo3, 2009 Rabatel et al., Cryosphere, 2013

28 GLACIER FLUCTUATIONS OVER THE 20th CENTURY Rapid area loss from 1970 Rabatel et al., Cryosphere, 2013

29 CUMULATIVE GLACIER MASS BALANCE ON TROPICAL ANDES TWO Tendencies: (1) Glaciers with a maximum altitude < 5400 m Average tendency of -1,2 m w.e./yr (2) Glaciers with a maximum altitude > 5400 m Average tendency of -0,6 m w.e./yr Rabatel et al., Cryosphere, 2013

30 THE VARIABILITY OF THE SEA SURFACE TEMPERATURE OF THE PACIFIC s The mass balance and the ENSO Particularly marker over the Inner Tropics (Ecuador, Colombia) Major events marked over the Outer Tropics (Peru, Bolivia) Rabatel et al., Cryosphere, 2013

31 1.INTRODUCTION 2. OBJECTIVES 3. STUDIED SITES 4. METHODS 5. RESULTS IN BOLIVIA 6. RESULTS IN SOUTH AMERICA 7. CONCLUSIONS AND PERSPECTIVES 31

32 CONCLUSIONS 1. All tropical glaciers are retreating from the late The speed has not PRECEDENT FROM THE LIA. 3. Glaciers over > 5400ma.s.l. (with an accumulation zone) have lost -0.6 mw.e. yr 1 in the last 30 years. 4. Glaciers above < 5400ma.sl have lost -1.2mw.e. yr -1 (the double rhythm of glaciers > 5400ma.s.l.). 5. The annual variability of mass balances is high, however negative mass balances are more frequent than positive mass balances. 6. The variability of the SST of Pacific's is the main factor controlling de annual variability of mass balances 7. The radiation fluxes(sw), controls the energy balance at the glacier Surface during the summer. Solid precipitation controls the seasonal changes of the energy fluxes (SW /SW ). 8. The precipitation has not significate tendency over the tropical Andes (Temperature, has rise at 0,10ºC decade -1 in the last 70 years). 32

33 Perspectives: Almost all the climatic scenario's Project the rise in temperature in the coming years (ex. IPCC AR5) (Gerbaux et al., 2010) 1º Glacier monitoring 2º Glacier Models (Energy Balance + Glacier Dynamics) 3º Glaciers simulations Under new climatic scenario s