HG · Metals / Water-Resource Supply Risk
Z32329 – HG Copper Peru Southern Aquifer
Aquifer depletion under the southern Peruvian copper belt constrains Las Bambas, Cerro Verde, Antamina, Toquepala, and Cuajone operations; the satellite water-storage reading leads copper price direction with a 60-day horizon.
At a glance
DORMANT · WAITING FOR SOU
Current reading
+0.757
Inverted 504-day z score of Peru Southern GRACE aquifer, tanh-bounded
SEASONAL STATE
DORMANT · WAITING FOR SOU
Signal state
Extreme POS
36 trading days in current state
Phase
HEALTHY
Positive equals water stress, negative equals water surplus
Sample
24 years
GRACE and GRACE-FO monthly release since 2002, roughly 6,152 trading days
As of Nov 04, 2026. Updated nightly. · NEXT WINDOW SOUTHERN-HEMISPHERE WET SEASON, DECEMBER THROUGH MARCH
SIGNAL OVERVIEW
Peru produces roughly 10 percent of the world copper, mostly from the arid southern highlands where mines like Las Bambas, Cerro Verde, Antamina, Toquepala, and Cuajone sit between 2,500 and 4,500 meters elevation. These mines consume on the order of a cubic meter of water per tonne of ore processed, plus dust suppression, tailings transport, and smelter cooling. When high-altitude aquifers deplete during La Nina drought cycles, production falls. NASA GRACE and GRACE-FO satellites have measured regional water storage every month since 2002. The composite inverts the anomaly so water stress reads positive. In July 2004 the composite rose into stress at the start of a 183-day run during the 2004 to 2005 La Nina drought, and copper rallied 11 percent in 60 days. In February 2012 the composite dropped to water surplus and copper fell 10 percent in 60 days. Today the composite reads +0.757, in Extreme POS territory.
LIVE CHART
Twenty-four years of Peru Southern copper belt aquifer stress from NASA GRACE and GRACE-FO.
The dark line in the top panel is the composite, bounded between minus one and plus one. The pale band at the top marks the water-stress regime where aquifers are depleted relative to their 24-year baseline; this historically precedes copper rallies at a 60-day horizon. The pale band at the bottom marks water surplus, which historically precedes muted or negative copper forward returns. The bronze line in the middle panel is the trailing 252-day rolling Spearman IC against copper forward 60-day returns. The lower panel is copper continuous back-adjusted price for market context.
COMPOSITE
+0.436 / tanh
STATE
Moderate Pos
PHASE
+1
FWD 60d
+2.75% (baseline +2.32%)
SAMPLE N
8,764 days
TODAY’S PLAYBOOK READING
STATE
Extreme Pos
STATE AND HISTORY
The signal reads modest aquifer stress against the trailing 2 year baseline. Not critical, but above typical.
WHY THE SIGNAL IS HERE
The GRACE anomaly data suggests Peru Southern aquifer storage is below the 2024-2025 baseline, consistent with reduced recharge from the 2026 ENSO-neutral regime.
POSTURE FOR THE WEEKS AHEAD
The signal is a slow-moving leading indicator. 6 to 18 month horizon. Current reading warrants attention to Peru-specific copper output news (Las Bambas operational guidance, Cerro Verde water permit renewals, Antamina production targets) and ENSO-regime forecasts.
WHAT THE CHART SHOWS
Today the composite reads +0.757, placing the dot inside the Extreme POS band on the top panel. Watch the mid-month GRACE release around the fifteenth for the atomic input; intra-month moves are forward-fill artifacts.
TOP INPUTS FIRING
- GRACE/GRACE-FO regional water anomaly Monthly satellite measurement of total terrestrial water storage over the Peru Southern bounding box, in centimeters of liquid-water-equivalent.
- 504-day rolling z-score Two-year scale of the inverted anomaly relative to its own history.
- Market phase direction Direction of the current state run, taken from the engine Market_Phase_Int column.
THE TAKEAWAY
What this means for you today
THE PHYSICAL MECHANISM
Peru Southern copper mines consume 70 to 150 cubic meters of water per tonne of concentrate. Multi-year aquifer depletion forces operational curtailments. GRACE detects these multi-year changes in groundwater storage directly from satellite, independently of operator-reported data.
WHY THE SIGNAL WORKS
Peru is the world’s second-largest copper producer (approximately 10 percent of global mined supply). Peru Southern copper belt alone represents 3 percent of global supply. Water-driven curtailments are historically significant: the 2003-2008 multi-year drought preceded Antamina output disruptions and contributed to the 2008 copper peak. The signal captures the slow-moving water-supply dynamics that daily satellite signals (NDVI, SMAP soil moisture) miss.
THE 2026 CONTEXT
Current reading reflects modest aquifer stress against the trailing 2 year baseline. Not critical. Reader attention to Peru-specific supply news is warranted but no urgent action implied. Pair with CHIRPS daily precipitation and ENSO-regime forecasts for ground-level validation.
THE REGIME MAP
The five regime states, forward returns and sample share
Baseline SPY forward 60 day return: mean plus 2.31 percent, median plus 3.14 percent, standard deviation 7.23 percent, percent negative 29.57 percent across 8,494 trading days. The signal’s primary target is copper forward returns.
| State | Phase | Share | Fwd 60d | HAC t | Edge vs baseline | Last firings |
|---|---|---|---|---|---|---|
| Water stress TODAY | +1 | 45.8% (2817 d) | +5.65% | +2.49pp | Sep 2026, Oct 2025, Sep 2024 | |
| Normal | 0 | 16.7% (1025 d) | +1.54% | -1.62pp | Aug 2026, Dec 2025, Sep 2025 | |
| Water surplus | -1 | 37.5% (2310 d) | +0.86% | -2.30pp | Feb 2026, Feb 2025, Mar 2024 |
The historical pattern
How to use the signal today
THE TRACK RECORD
State changes
| State | Start | End | Duration | Fwd 60d COMEX HG |
|---|---|---|---|---|
| Extreme Pos (aquifer Stressed) | 10/28/2024 | 01/31/2025 | 66d | +3.19% |
| Normal | 02/03/2025 | 02/26/2025 | 17d | -7.23% |
| Extreme Neg (aquifer Wet) | 02/27/2025 | 09/02/2025 | 129d | -1.02% |
| Normal | 09/03/2025 | 09/30/2025 | 20d | +5.77% |
| Extreme Pos (aquifer Stressed) | 10/01/2025 | 12/23/2025 | 59d | +3.27% |
| Normal | 12/24/2025 | 02/10/2026 | 32d | -5.39% |
| Extreme Neg (aquifer Wet) | 02/11/2026 | 08/21/2026 | 133d | +6.60% |
| Normal | 08/24/2026 | 10/01/2026 | 28d | |
| Extreme Pos (aquifer Stressed) | 10/02/2026 | 10/26/2026 | 17d |
Scroll inside the table for the full history. Forward 60-day COMEX HG is measured from each run’s start date; a reader cannot trade off a start-date they only identify in hindsight, so this is a transparency log, not an alpha claim. Asterisked (*) returns are partial. The run is less than 60 trading days old. The full 60-day comparable fills in as more data arrives.
What this measures
Peru produces roughly 10 percent of the world copper supply from the southern highlands; Las Bambas, Cerro Verde, Antamina, Toquepala, and Cuajone depend on high-altitude aquifers and glacial melt for flotation, tailings transport, and smelter cooling. When the aquifer under this belt depletes, production falls. NASA GRACE and GRACE-FO satellites measure regional water storage every month since 2002. The composite inverts the anomaly so stress reads positive, z-scores over 504 days, and bounds through tanh.
Why it matters
Las Bambas, Cerro Verde, Antamina, Toquepala, and Cuajone operate between 2,500 and 4,500 meters in the arid southern Peruvian highlands. All five depend on aquifers and glacial melt for flotation and tailings transport. When La Nina droughts deplete the regional water table, mining throughput follows on a 2-to-6-month lag.
Stress above the plus 0.6 band has historically preceded copper fwd-60-day returns well above baseline. Pair with physical-market indicators (LME copper stocks, concentrate TC/RC charges) to confirm supply tightness is landing in the chain.
The 2016 to 2017 reflation episode saw copper weaken despite a 163-day water-stress run, as macro demand concerns and the strong dollar dominated. This is a supply-side read; macro-demand shocks can and do overwhelm it on any given cycle.
GO DEEPER
Want the full depth?
The brief covers the GRACE and GRACE-FO instrument design, the bounding-box methodology over the five Peruvian mines, three signature episodes (2004-2005 La Nina drought launching the supercycle acceleration, 2012 water-surplus coincident with the China slowdown, 2016-2017 reflation-era water-stress run), and the four caveats on reading a monthly satellite signal as a daily tape. Includes regime-conditional forward returns and the 60-day horizon decomposition.
Signal consumers and siblings
Not investment advice · The analysis on this page is informational and educational. Signal readings, historical case figures, and empirical statistics are derived from publicly available data and are provided without warranty. Hypothetical performance results have inherent limitations, including the benefit of hindsight. Readers who intend to trade should consult a licensed investment professional and see the research brief for the full disclaimer.
Last refreshed Nov 05, 2026 08:13 PM ET