Will global warming put an end to the need for snow clearance at major airports, except for a few places in the Polar regions? Absolutely not, says Airside’s Chris Lewis. World temperatures may be rising, and there could well be fewer days with snow in many parts of the world, but snow still has the ability to take airport authorities, transport operators and even weather forecasters by surprise.
When it does come, snow still has the ability to completely shut an airport down if it is not properly equipped, or if adequate plans are not in place. Coupled with this is the intensity of today’s air traffic. Whereas in the past global aviation might have been able to function with the odd runway here and there closed by snow, the system is much less tolerant today. Runways must be kept open if humanly possible.
So the demands on snow clearance equipment will, if anything, arguably be greater than in the past.
Weather is, of course, notoriously hard to predict. It’s impossible to know exactly what the weather will be tomorrow – even less so in 72 hours’ time. Even in those regions where winter snow is a given, can we know exactly on what date the first heavy fall of the year will be?
Still less is it possible to gauge with any certainty what long-term trends in weather, or snowfall, will be. Writing in 2011 in the blog of research organisation Climate Central, just after the US East Coast had experienced a particularly heavy snowfall, weather expert David Kroodsma said that the best answer he could give to the question: ‘Is climate change making snowstorms worse?’ was: “Maybe.”
Global warming might be reducing average seasonal snowfall over time, but from an airport perspective what is of equal interest is whether that snowfall comes from many small storms or fewer, bigger ones. In fact, the US East Coast had just seen an abnormally high number of major storms – defined as storms that dropped more than 10 inches over large areas – Kroodsma said.
Both 2009-10 and 2010-11 had three winter storms that qualified as at least a Category 3 based on the Northeast Snowfall Impact Scale, whereas the severe 1995-96 winter didn’t have as many storms of that ranking, and you’d have to go back to 1960-61 to find as many high-scoring winter storms in a single season as seen in each of the past two years.
But at the UK’s Met Office – one of the leading global authorities on weather – aviation scientist Claire Bartholomew says she does not think there is currently sufficient evidence to support the theory that snowfalls are getting less frequent but more intense. Although there is a projected reduction in the number of days with snow, there is still a huge amount of regional variation and the amount of snow can fluctuate enormously from year to year.
There is a lot of interest in general weather trends in the aviation industry, she adds – not just snow but effects like turbulence or convection. And while there has been considerable research on the effects of climate change, there have not yet been too many studies looking at its impact on aviation specifically.
Of course, there are parts of the world where it’s a reasonable assumption that there will never be sufficient snowfall to justify investing in heavy-duty clearance equipment. A spokeswoman for Dubai Airports (yes, it has snowed in the UAE in recent memory, a couple of times in the past two decades or so) says that neither of the major airports there has invested in equipment because snow is such an infrequent event.
But in other parts of the world it is very different. Dan Meincke, director of traffic and airside operations at Copenhagen Kastrup airport, points out that it is often the speed, rather than the amount of snow that causes issues. “We have lots of sea around our airport, so we have something we call ‘snow bombs’ – and global warming will increase this phenomenon. Snow bombs can occur right next to the airport and we often have only 20-30 minutes to be ready for 10-20cm of snow.” Basically, cold air blowing over relatively warm water creates lots of snow, which the prevailing wind then deposits over Kastrup.
Like other airports, Kastrup aims to be open 24 hours a day, every day of the year, so employees in many other departments – firemen, bus drivers, marshals and others – lend a hand during snowfalls. Meincke observes: “We have employees with a lot of soul and spirit, and that means a lot.”
Kastrup favours eco-friendly, multifunction vehicles that can be used for both summer and winter operations, “easy-to-maintain, standard products” that are straightforward to maintain and which use readily available, standard spare parts. “We try to be eco-friendly, with particulate filters, alternative fuel solutions,” Meincke notes, adding that autonomous robotic equipment may be of interest in future.
Likewise in the US, Denver International Airport (DEN) also favours multifunction equipment, which it says is “a primary requirement to ensure more capability with a smaller fleet”.
New stricter emission regulations have now been fully implemented at Denver which means that engines’ emission systems have been more complicated by after-treatment systems such as particulate filters and diesel exhaust fluid (DEF); managing DEF is a new issue both for operators and technicians.
But the new multifunction snow units offer improved performance and potentially could mean savings on labour costs: GPS and telematics allow better tracking of vehicle movements and route planning, while also monitoring vehicle idling statistics.
Aero Snow Removal is Denver’s ramp snow removal contractor. The airport does though manage its operation in terms of the quantity of equipment and number of staff required, start and stop times, and when snow melters are mobilised.
As with major gateways, Denver’s expectation is never to close if at all possible. As to whether snowfalls are getting more unpredictable, Denver had 78 inches of snow three years ago and 72 inches last year, “so it’s been fairly consistent”.
Bob Kerlik, vice president of media relations at Allegheny County Airport Authority, which operates Pittsburgh International Airport on the US East Coast, says that among the many factors to consider in buying snow clearance equipment are reliability, reputation, parts availability and price. “We want a machine to last 20 years that meets 100% of the required specifications,” he explains.
Some airports are looking to multifunctional pieces of equipment but others are quite happy with two separate apparatuses, he adds. New equipment has to meet Tier 4 emissions standards, “which leaves some unknowns of what the impact will be on the engines of these large pieces of equipment,” Kerlik points out. There are also considerations in managing de-icing fluid run-off, he adds. New equipment also tends to feature GPS and electronic chemical tracking, using modern sensors and computers on vehicles.
PRIOR PREPARATION AND PLANNING
But preparation is everything in successful snow clearance, Kerlik says. Pittsburgh usually starts its planning in August, to prepare for the first anticipated snow event in late October or early November. Equipment preparations for the following year start after the last snow event of the season, usually March, with preventative maintenance checks and necessary repairs. Sufficient supplies are stockpiled prior to the season and replenished as required.
‘Dry-run’ training is also performed to refresh employees prior to having to deal with an actual winter event.
Each winter season is different and a winter plan is prepared annually and reviewed by all. Weather experts are also contacted prior to the season for short- and long-range forecasts and they are consulted at least three times per day for updates to conditions, expectations and changes.
Kerlik points out that while very few airports in the US permit contractors on the actual airfield, gate areas are typically cleared by airlines with their own equipment – or they may use contractors.
Snow can, of course, cause problems on the roads and transport systems outside the airport, which could prevent vital employees making it in to work to perform snow clearance duties. So, when a major weather event is expected, crews arrive beforehand and are prepared to stay throughout in emergency accommodation – which include a kitchen and bunk rooms at Pittsburgh to allow personnel to stay on site as long as necessary.
As for whether staff can make it to the airport in the first place, Kerlik notes that the gateway is surrounded by interstate highways, which are typically well cleared by the state authorities. (It’s often said that places that experience a lot of regular snow cope better than places in temperate climates like London, where snow is less predictable and the road authorities less well equipped, or possibly less ready, to deal with it.)
Is there now more of an expectation that airports must stay open, whatever the weather? Kerlik opines: “It’s always been that way in the US and at Pittsburgh International Airport. The national airspace system is heavily impacted if any airport closes. Safety and security are always the top priorities at Pittsburgh International and we take pride in the great snow removal reputation here.”
Also in the US, the Port of Seattle – which manages the local airport, Seattle-Tacoma (Sea-Tac) – looks for “a cost-effective and safe means for clearing snow and ice. We look for modern, multifunction equipment that is operator-friendly, meets our strict emission standards and can be upgraded as technology evolves.”
There aren’t really any environmental or emission standards for snow removal equipment as such, it says, but the airport tries to find the most environmentally friendly machines available while still maintaining high operation standards. Seattle, in fact, rarely gets snow but calls in contractors when two inches or more are forecast; they are called to stage equipment prior to that event.
Global warming or not, Zurich Airport “always needs to be prepared for long and heavy winters”. Despite its situation in the heart of the Alpine region, it proudly boasts that it has never had to close its runways during winter or due to weather disruption.
Even here, though, snow clearance equipment has to pay for its keep. One criterion in its selection process is that it should be usable for other tasks during the off-season.
As well as fulfilling safety and environmental criteria – although Switzerland is outside the EU, Zurich looks for equipment that complies with EU norms in terms of pollution and noise – other factors to consider are price (both the purchase price and the cost of maintenance during its life cycle), how long the delivery of spare parts takes and even the quality of the instructions provided.
New equipment also needs to be compatible with the current fleet, easy to handle, offer good performance – and it should be corrosion-proof.
Overall, the lifecycle of equipment at Zurich is anticipated to be between 20 and 25 years, says the airport.
Wherever possible, Zurich Airport invests in alternative technologies such as electric drives, but as continuous operation during winter is a main goal, any new technologies have to be at least as reliable as the older ones.
Munich Airport, as a major German intercontinental hub, puts much effort into ensuring that it remains open, even during difficult weather conditions, says aviation vice president Alexander Hoffmann. The gateway has invested “to a great extent in the purchase of state-of-the-art winter service equipment, weather forecast technologies as well as the continuous training of employees”, he reports.
As well as meeting technical and operational requirements, the acquisition costs and annual maintenance costs are important and, not least, the lower the CO² emission the better (at least ‘Euro 5’ standard).
On-call or on-demand provision and service of staff, vehicles and material is, however, becoming more and more challenging, Hoffmann continues. Moreover, the co-ordination and interfacing with all entities involved in winter service – air traffic control, weather service, apron control, airlines and aircraft de-icing – is more complicated and comprehensive due to extreme weather conditions which can occur more rapidly and intensely. Around 90% of snow clearance and removal at Munich Airport is outsourced to subcontractors but controlled and co-ordinated by the airport’s directors of operation.