Journal
Our hub for snowmaking advancements, polymer discovery, and operator insights.
Mitchell McLennan
The peer-reviewed case against snowmaking as adaptation: what the data supports, what it overstates, and the efficiency variable both sides skip.
ReadMitchell McLennan
The two snowmaking metrics that matter: kWh per m³ of snow and m³ of water per m³ of snow — plus the density and wet-bulb basis that makes them comparable.
ReadMitchell McLennan
The snow-reliability line sat near 1,200 m in the Swiss Alps and rises ~150 m per 1 °C of warming — why elevation decides which resorts survive.
Mitchell McLennan
A snow gun makes roughly 50–250 m³ of snow per hour in good cold — but output is a conversion set by water flow and wet-bulb temperature, not a fixed spec.
Mitchell McLennan
Machine learning can design ice-binding molecules — it's been demonstrated. But the tools generate and rank candidates; the wet lab still decides.
Mitchell McLennan
Wet machine snow means droplets did not fully freeze in flight — a wet-bulb and humidity problem. How to read it and fix it at marginal temps.
Mitchell McLennan
A polymer additive changes how snow forms, not what it is — drier, denser, more durable snow in the marginal window, and trace polymer at ppm.
Mitchell McLennan
Peer-reviewed work projects as few as 14-24 French Alps and Pyrenees resorts snow-reliable on natural snow by 2050 - and 83-116 more viable only with snowmaking.
Mitchell McLennan
The polyacrylamide in a snow additive is the same class used to clarify drinking water — a stricter application. The 0.05% monomer bar, explained.
Mitchell McLennan
How the cold-water-swelling starch in a two-part polymer additive floods the droplet stream with physical nucleation sites - the non-biological counterpart to a bacterial nucleant.
Mitchell McLennan
Snow lances sip energy on cold terrain; fan guns reach the marginal wet-bulb window. How to choose per trail - and why an additive complements either, with no capex rip-and-replace.
Mitchell McLennan
The honest environmental case for anionic polyacrylamide in snowmaking: ppm dosing, low aquatic toxicity, a 30-year USDA record — and the not-readily-biodegradable caveat.
Mitchell McLennan
30 cm, 100 days, 7 winters in 10 - the benchmark that decides snow reliability, the elevation line beneath it, and why the marginal wet-bulb window decides a resort's future.
Mitchell McLennan
Thermal hysteresis and ice recrystallization inhibition are decoupled properties of antifreeze molecules. Why IRI, not TH, is the one that matters for snow.
Mitchell McLennan
Drier, more groomable machine snow comes from four controllable levers plus chemistry. An operator's guide to snow quality at marginal wet-bulb temperatures.
Mitchell McLennan
The regulated hazard in a polyacrylamide additive is residual acrylamide monomer, not the polymer. Why 0.05% is the ceiling that matters for snowmaking water.
Mitchell McLennan
Roughly 90% of Italy's ski terrain and 75% of Austria's is covered by snowmaking. Why made snow is now the base, not the backup — and what that implies.
Mitchell McLennan
α-Alanine is the smallest known ice-recrystallization inhibitor — 13 atoms. Why the tiniest antifreeze molecule shapes how synthetic AFGPs are designed.
Mitchell McLennan
PFAS in skiing is a ski-wax problem, not a snowmaking one. No snowmaking additive contains PFAS — and why SL6733 is PFAS-free and biology-free.
Mitchell McLennan
Snow gets icy with age through Ostwald ripening — large ice crystals grow at the expense of small ones. How recrystallization inhibition slows it.
Mitchell McLennan
Missing the Christmas–New Year window can cost a ski resort ~20% of annual revenue. Why the holiday weeks carry the P&L, and how snowmaking defends them.
Mitchell McLennan
The snowmaking equipment market is ~$2B, but that understates the opportunity. Here's the full value chain — from hardware to the ski economy made snow protects.
Mitchell McLennan
EU water law doesn't ban snowmaking additives — it sets water-quality outcomes and leaves permission to member states. Here's how the WFD and Drinking Water Directive actually apply.
Mitchell McLennan
Ice nucleation is the trigger step in snowmaking — the moment supercooled water freezes around a seed. It sets a snow gun's warm-weather limit. Here's the physics.
Mitchell McLennan
Artificial and natural snow are the same water, but form differently. Machine snow is up to 10x denser, lasts longer, and its quality is controllable. Here's the science.
Mitchell McLennan
Snomax is owned by TechnoAlpin, the largest snow-gun OEM, acquired in 2012 via Johnson Controls Neige. Why that vertical integration froze additive chemistry.
Mitchell McLennan
Snowmaking demand is projected to rise 55-97% by 2050 in tightening catchments. Which water levers actually reduce draw — and which just move it.
Mitchell McLennan
Snowmaking is ~17% of daily opex at large Swiss resorts and front-loaded into the months before revenue. What the line item contains and which levers move it.
Mitchell McLennan
Polymers are exempt from REACH registration under Article 2(9) — their monomers carry the burden. Why "REACH-approved" is not a thing, and what does apply.
Mitchell McLennan
Does a US snowmaking additive need EPA approval? How the 40 CFR 723.250 polymer exemption works, and why an anionic PFAS-free polymer is a candidate.
Mitchell McLennan
How ppm dosing works for snowmaking additives: 1 ppm is about 1 gram per cubic metre. A polymer additive doses at 6–7.6 ppm, metered upstream of the guns.
Mitchell McLennan
Cut snowmaking cost per cubic metre — not output. The five levers: wet-bulb timing, pumps, automation, water reclamation, and additive chemistry.
Mitchell McLennan
A snowmaking manager's checklist for evaluating an additive: regulatory fit, chemistry, dosing, wet-bulb gain, safety, and value-based pricing — in order.
Mitchell McLennan
An extra open day is worth what its date commands — peak-holiday days are a large multiple of shoulder days. Why the average misleads, and why it points to value-share pricing.
Mitchell McLennan
Snowmaking extends a ski season at both ends — earlier openings and spring durability — by converting marginal wet-bulb hours into open days. How it works, and where the limits are.
Mitchell McLennan
Biological additives (Snomax) nucleate ice; polymer additives nucleate and inhibit recrystallization. The two chemistries diverge on mechanism, snow quality, and regulatory pathway.
Mitchell McLennan
Austria and Bavaria bar all snowmaking additives — biological and polymer alike — under water-protection law. Not an EU ban: a regional 'water only' rule, explained honestly.
Mitchell McLennan
The peer-reviewed data on snow reliability, resort risk, and why snowmaking is the decisive adaptation - François 2023, Spandre, Abegg, IPCC, read straight.
Mitchell McLennan
Snowmaking uses ~2,900-4,000 m3 of water per hectare per season (~1 acre-foot per acre). Where it goes, why most returns to the watershed, and how to use less.
Mitchell McLennan
How Snomax works: inactivated Pseudomonas syringae and its ice-nucleation protein, what the risk assessments really found, and where it is restricted.
Mitchell McLennan
No - polyacrylamide is not readily biodegradable. But it is non-bioaccumulative, low-toxicity, and dosed at ppm. The honest environmental profile, for snowmaking.
Mitchell McLennan
Austrian snowmaking uses ~281 GWh a season and can be half a resort's early-season power bill. Where the energy goes, why it rises in warm spells, and how to cut it.
Mitchell McLennan
All-weather machines make snow at any temperature but use 6-65 kWh/m3. A polymer additive widens the window of your existing guns at ppm cost. The economics, compared.
Mitchell McLennan
There is no EU-wide ban on snowmaking additives. A country-by-country reference: where additives are prohibited, discontinued, or permitted — and why.
Mitchell McLennan
Too warm to make snow usually means too warm for the guns as run. The operator playbook for the marginal wet-bulb window - and where the hard limit sits.
Mitchell McLennan
Snowmaking cost is dominated by energy, not water, and it rises sharply as the air warms. A sourced breakdown of the cost per acre-foot and where savings hide.
Mitchell McLennan
What a polymer snowmaking additive is, the three jobs it can do inside a snow gun, how it differs from Snomax, and why the category is changing now.
Mitchell McLennan
Ski resorts cut snowmaking water and energy with four levers. There is a fifth almost nobody names: additive chemistry that lowers water and energy per m3 of snow.
Mitchell McLennan
ANSES rated artificial-snow risk 'null to negligible' and flagged source-water microbiology, not the additive. The primary document, read straight.
Mitchell McLennan
SL6733 is a two-component polymer snowmaking additive: an anionic PAM-co-acrylate plus a starch nucleant, dosed at 6–7.6 ppm for a modelled +3 °C wet-bulb advantage. What it is, how it works, and where it fits.
Mitchell McLennan
Snomax is not banned across the EU. It is restricted by national measures — discontinued in France, prohibited in Austria and Bavaria, approved in Italy, Switzerland and the US. Here's the accurate picture.
Mitchell McLennan
Snomax is the dominant biological snowmaking nucleator — and it is restricted across France (2005 moratorium), Austria, and Bavaria. This is the complete guide to the alternatives: how Snomax works, how the Drift surfactant compares, and how SL6733, a synthetic polymer engineered for the EU polymer exemption, addresses the regulatory gap.
Mitchell McLennan
A field guide to the snowmaking-additive category — biological nucleators, polymer-based systems, wet-bulb economics, EU regulatory framing, and what operators should evaluate when picking a chemistry.
Mitchell McLennan
IRI is the mechanism that controls how ice crystals grow once formed. It is why snow density, durability, and melt rate vary so much between additives. Here is the physics, the chemistry, and what makes a polymer effective at it.
Mitchell McLennan
DS-100 is DeepSnow's R&D-stage polypeptide chemistry — alanine/glutamate alternating, NCA polymerization, 91–94% MGS reduction at 100 µg/mL. The discovery engine is what produces it.
Mitchell McLennan
A field note on how DeepSnow operates: wet lab + AI discovery engine + product portfolio, vertically integrated, and what compounds when chemistry and software run in a closed loop.
Mitchell McLennan
Wet-bulb temperature is the thermodynamic ceiling of conventional snowmaking. Here is what it is, how to measure it, why a +3°C improvement is worth $2.4–2.8M EBITDA per resort per season, and how additives change the math.
Mitchell McLennan
A working-level reference for the regulatory frameworks that apply to snowmaking additives across the EU, Switzerland, and the US — including the active Snomax bans in Austria, France, and Bavaria.
Mitchell McLennan
Under the central IPCC warming scenarios, 98% of European ski resorts are at risk by 2050. Here is the climate-data structure of that risk, what season-length compression actually looks like, and which adaptation tools work.
Mitchell McLennan
A wet lab, an AI polymer discovery engine, and a shipping product portfolio — led by SL6733, a +3°C wet-bulb snowmaking additive.