April 2013

Water Proof

Scientists join fishermen, boaters and shore-dwellers to document profound changes on Lake Champlain. Are shrinking ice and rising water the new norm for the North Country?

Photograph courtesy of Russell Fox

In July 1609 Samuel de Champlain wrote in his journal while traveling the length of a large lake with a group of Native Americans: “I noticed, while observing the country, some very high mountains on the eastern side, on top of which there was snow.”

In describing a summer visit to upstate New York in 1791, Thomas Jefferson wrote that local residents told him that the same lake, which by then was known as Lake Champlain, “closes with ice about the last of November.”

These are among the earliest recorded observations of the Champlain Basin’s climate, made during a natural, relatively cool period known as the Little Ice Age, between the 15th and 19th centuries. Today, another two centuries later, snowcaps on the Green Mountains in July and ice on the main basin of Lake Champlain in November are things of the past. And people who live, work and play on Lake Champlain are witnessing more dramatic changes within their own lifetimes. New scientific evidence supports what anglers, sailors and ferry operators are noticing about declining ice cover, shifting lake levels, and other signs that unnatural, human-driven climate change has come to the North Country in ways that are increasingly difficult to ignore.

The retreat of ice cover on Lake Champlain is perhaps the clearest measure of such change. A 200-year sequence of freeze-up dates shows that the main basin froze over during every winter but three during the 19th century. Normally, freeze-up came in January or February, already much later than what Jefferson reported. Was it because the climate was already warming by then, or did Jefferson’s sources refer merely to some bays that froze earlier and more easily?

We can’t be sure of the answer, but one thing is both more certain and more relevant to us today: during the 20th century Lake Champlain failed to freeze completely 27 times, and most of those ice-free winters occurred since 1970. Now, in the first years of this new century, total freeze-up is no longer the rule but the exception.

Only two things are likely to cause a long-term advance in freeze-dates like this: wind and temperature. There is no historical evidence that winds have strengthened and stirred the lake surface enough to slow the formation of winter ice in this manner. However, local weather records do clearly reveal a parallel increase in air temperatures during the last century.

In 2010, as part of a study for the Nature Conservancy’s Adirondack and Vermont chapters, I looked at historical temperature records from eight weather stations throughout the Champlain Basin. Between 1976 and 2005, average air temperatures over the basin rose by 2.1 degrees Fahrenheit. The warming in autumn was even greater, which is consistent with the pattern of later freeze-ups on Lake Champlain. Minor irregularities in the warming pattern also fit those in the ice record. A temporary pause in the warming trend during the 1960s, partially attributable to clouding of the atmosphere with soot and other pollutants, paralleled a temporary drop in the number of ice-free winters.

Not surprisingly, the lake itself has been heating up, too. In a study published recently in Journal of Great Lakes Research that was based on data from 10 monitoring stations around the lake, notable warming of the surface occurred between 1964 and 2009, including a three- to seven-degree rise in August water temperatures at eight of the 10 sites. And the authors were not surprised to learn that the water has warmed even faster than the overlying air, be­cause the same pattern has been ob­served in other lakes around the world. In what appears to be a smaller, down-home version of the de-icing of the Arctic Ocean, the retreat of Lake Champlain’s ice exposes the underlying water to additional heating from the sun. Atmospheric warming drives ice loss, which en­hances lake-warming further, which loops back around in a spiral of stimulus and response that amplifies the pace of change here.

What does the future hold? Climate models, the laws of physics, and common sense agree that global warming will continue as long as greenhouse gases continue to accumulate in the air. Experts also agree that it will take many centuries for slow absorption by the oceans, rocks and soils to return atmospheric carbon dioxide to pre-industrial levels.

The amount and rate of change here depends on how much coal, oil and gas are burned and which of many models you trust the most; on our present trajectory, we could be facing as much as 11 degrees of additional warming here by the end of this century. Natural random fluctuations in our variable North Country climate will kick temperatures up or down a bit from year to year as always. But the long-term direction of change is clearly upward, on average, for the foreseeable future.

Temperature is not the only variable in play. Precipitation and wind are also important aspects of climate, though they haven’t gotten as much attention until recently.

In April and May 2011 Lake Champlain surged to 103.2 feet above sea level, shattering all previous records and inundating fields, forests, roads and buildings, including early-19th-century houses that had never been wetted before. An unusual mix of heavy spring rains and copious snowmelt poured hundreds of billions of gallons of water into the lake. According to the Lake Champlain Basin Program, more than 60 square miles of shoreline were inundated at the peak lake elevation. The lake remained above flood stage for more than two months.

The following August, Hurricane Irene failed to smash New York City as expected and was downgraded to tropical storm status. As public attention turned elsewhere, people seemed to forget that high winds aren’t the only danger from such storms. This one crept up the Hudson Valley, squatted over the Champlain region and dumped more than a foot of rain over the course of a single Sunday. As mountainous watersheds are wont to do, this one shed the torrent so rapidly that it turned local streams and rivers into raging monsters. Towns, farms and homesteads were devastated, critical roads and bridges were destroyed, and tons of sediment and debris poured into Lake Champlain.

Then came the winter that wasn’t. Bears and raccoons that normally sleep through the winter remained active in a barren landscape that offered them little or no food. In March, the jet stream—a meandering river of westerly wind that circles the globe between us and the North Pole—warped itself into an enormous loop that lassoed a bubble of warm air from the southern states and tied it down over the North Country for more than a week. Temperatures soared into the 70s, flowers and insects woke up early, and people shed their winter coats. But it was all a cruel lie. Soon after, the cold returned as fierce as ever.

Then followed a strangely dry summer that dropped the level of Lake Champlain below normal. By autumn, as Hurricane Sandy inundated New York City, people around here were already wondering what was going on with the weather.

Is this global warming?

A good scientist must answer that question with a lousy answer: “We can’t say for sure.” Some of this wildness is just bad luck, an unfortunate toss of the weather dice. But global warming has now loaded those dice, and the chances of them coming up double-sixes are growing ever larger. Some are calling it “global weirding” as erratic extremes become more extreme. Or, as Eric Pooley, of the Environmental Defense Fund, recently put it, “We can’t say that steroids caused any one home run by Barry Bonds, but steroids sure helped him hit more and hit them farther. Now we have weather on steroids.”

This isn’t just some abstraction that comes from a computer model or a distant corner of the world. In the wake of the 2011 floods, I examined daily rainfall records from the weather stations in Dannemora, New York, and Colches­ter, Vermont, and found a disturbing pattern. Storms that dropped two inches or more within a 24-hour period have become more frequent at both locations during the last century. And the magnitudes of the heaviest deluges have in­creased as well, just as climate models predict when a warming at­mosphere sucks more moisture from warming oceans.

Rather than try to link this or that particular event directly to global warming, however, a more useful ap­proach is to learn from it. If the last two years of deranged weather have anything close to a silver lining in them, it may be what educators call a “teachable moment.” This—according to the models, the studies and the historical records—is what global warming in the North Country looks like. It would be wise to remember these lessons as we also struggle to recover from them.

Take lake levels for example. The surface of Lake Champlain is, on average, a foot higher now than it was before 1970. That change coincided with a three-inch jump in mean annual precipitation in the watershed, and records dating back to 1940 show a close link between lake level and precipitation from year to year. With the moisture content of the atmosphere and the in­tensity of major storms likely to in­crease in coming decades, it’s reasonable to expect Lake Champlain to flood its banks more often and more extensively in response. Perhaps we should consider this to be our own local, mountain version of sea-level rise and plan accordingly.

In an ironic twist, the high lake levels of 2011 kept most watercraft on shore because major launching facilities were underwater. Ferries stood so high above their flooded docks that crushed rock had to be shoveled into temporary ramps to allow cars to drive on and off. Floating trees and assorted wreckage from surrounding settlements swept into Lake Champlain and became navigation hazards. Sediment piled up in river deltas. Such are the hard lessons that were delivered and, fortunately, many of them are being recorded for future reference before memory fades.

A Lake Champlain Basin Program map highlights in bright orange the zones that will be most vulnerable the next time we face spring flooding like that of 2011. The illustration is only preliminary—the inundation zones are based on topographical features rather than detailed satellite imagery of the 2011 flooding—but it’s a good start. What’s needed is a more rigorous local mapping program akin to those that have already charted the areas most vulnerable to global sea level rise.

The historical relationship of approximately three inches precipitation to one foot lake level rise on Lake Champlain suggests that an anticipated four- to six-inch increase in annual precipitation by 2100 AD could lift the average level of the lake another foot or two. Today’s extremes will seem more and more like business as usual in a warmer, wetter future.
Citizen scientists are now being rallied to help monitor conditions in the lake as its climatic setting changes. The Lake Champlain Committee deploys local volunteers to track the growth of toxic plankton blooms that can result from summer warming and the phosphorus pollution in river runoff, making weekly reports. Results are posted online. We need more of this kind of thing, which follows in the time-honored tradition of Samuel de Champlain and Thomas Jefferson, and which can supplement more formal research programs that monitor the environmental changes that are now underway.

But the most indelible lessons are more personal and immediate. In a workshop adjacent to the harborside office of Lake Champlain Ferries in Burlington, Vermont, marine superintendent Russell Fox showed me a wall marked with a series of horizontal lines that serve as reminders of past invasions by the lake. The four that lie closest to the floor show a progressive rise of high water marks in 1970, 1971, 1972 and 1976, following the stepwise in­crease in annual precipitation in the Champlain Basin around 1970. A fifth line, however, stands thigh-high on Fox, well above the others. It’s marked “2011” as a reminder of what, sooner or later, is sure to come again.

This landscape that once knew snow­­caps in summer and freeze-ups in Nov­ember is still a ruggedly beautiful place to live, and it will likely remain so. But it will also be a different world from the one we’ve become used to, an in­creasingly warmer one with less ice and more intense storms. After watching Irene and Sandy wreak havoc on both ends of the strip of land between Manhattan and Montreal, New York governor Andrew Cuomo summed up our situation with characteristic candor: “It’s not prudent to sit here and say it’s not going to happen again. I believe it is going to happen again.”

Most communities in the North Country now recognize the wisdom of those words, as does the scientific community worldwide. Like the climate itself, our public conversation is changing as we switch from asking, “Is it happening?” to a more practical and productive, “What are we going to do about it?” Answering that new question will be one of the greatest challenges of our time, and as the tale of how we answer it unfolds, it is likely to dominate the subtext, if not the central story line, of our own unique chapter in history.

Eyewitness accounts from fishermen, boaters and long-term observers of change on Lake Champlain
These excerpts are from interviews that have been edited and condensed

Mike Wojewodzic, 63
Meat fisherman
Mineville, New York

Mike Wojewodzic has fished the narrow, relatively shallow southern end of Lake Champlain all his life. He fishes for his table and sometimes sells his catch.

My father used to take us out on the ice, when I was five years old or so. They didn’t have the modern technology like the power auger, so they chipped through the ice with a chisel. We used to put tip-ups out and fish in the shanty for the smelt or perch, whatever we could get. That went on until the smelt population went downhill gradually, I’d say the last four years especially.

Back in the hard times, when people didn’t have a lot of money, they used to barter. My mother and father, they would sell or barter fish for meat. Smelt used to get shipped out to New York City. Tons and tons went out by rail. It used to be a big industry here.

That’s how a lot of guys survived when work was scarce, and during wartime and right after World War II.

Alewives are a competitor for the same things smelt eat. Especially at the southern end of the lake the smelt don’t come here anymore. I don’t know if they are staying up in the deeper water, but the smelt are kind of gone down here.

People would give their left arm to have the smelt back. There was a lot of camaraderie … the whole community got together out there on the ice, really.

The global warming, you don’t get the ice you used to. It used to look like a city with the shanties out there. A guy used to plow roads around the whole area so people could get out there with their vehicles and fish. The ice used to be three, four feet deep.

Last year the ice didn’t freeze up even to the Port Henry beach. The ice has been weird, a lot of unsafe ice the past few years because it’s been so warm.

Another thing that’s killing the area lately is access to the ice. If it doesn’t freeze up to the [Bulwagga Bay] campsite, the only way to get to the ice [in the bay or the narrows] is across the railroad tracks near the rock cuts. But the railroad doesn’t want to allow access because of the liability.… You’ve got no legal access to get to the ice from Crown Point to Ticonderoga.  

Russell Fox, 47
Marine superintendent,
Lake Champlain Ferries
Burlington, Vermont

Russell Fox has worked on the water and shore of Lake Champlain for 31 years.

The long-term change in the ice has been slow here, kind of like watching your kids grow day by day. But it’s def­in­itely noticeable over time.

The whole lake still used to freeze over until five or six years ago, but it’s been staying open out in the middle nowadays.

The change affects the ferry traffic. The calmest conditions for travel are when there’s a quick freeze-up that’s easy to break a channel through. Under those conditions there are no waves to deal with and the ferries have no trouble keeping the thin ice in the channels open from day to day.

When there’s no ice out there, it can be rough on windy days and during storms. The worst conditions are when the winds blow lengthwise down the lake and build up huge waves, and December and January are the roughest months. Some pilots say that they can also feel a difference during the winter because the water is colder and denser. The waves knock you around more than usual then, and that can make for a rougher ride.  

The rise in the lake levels has also been kind of a slow-motion blur over time, except for the really extreme situations like we saw in the spring of 2011. When the lake first overflowed here, it wasn’t too bad. We rowed people to and from work in the main office when the parking lot flooded. Here in the shop, we worked all day in hip waders. Then the lake rose higher, and people switched to chest waders. After almost two months of chapped legs, and slogging through the cold water, and flooded bathroom facilities, we didn’t like it much at all.

A sudden flood comes and goes and when it’s over you just deal with it. But slow flooding is harder to handle. You watch the water come up higher and higher day after day, and it just gets worse and worse. It really wears on your psyche. 

Mick Maynard, 55
Sport-fishing charter captain and guide
Plattsburgh, New York

Mick Maynard grew up at Chazy Landing and has been fishing Lake Champlain since he was old enough to hold a rod. He has run Lake Cham­plain Angler Fishing Charters for six years.

We’re getting more violent storms. When it’s hot it’s really hot, when it’s dry it’s really dry, when it rains it really rains, and when the wind blows it really blows. I made this observation well over ten years ago, just from a fisherman’s point of view. We knew what we were out in, and it was tougher conditions for fishing. To be sure, the environment is changing.

We’re having more of what they call 100-year flood events that are causing erosion. The major tributaries in Lake Champlain have ridiculous sedimentation in their deltas. Even the smaller ones have sedimentation in them. They are almost to the point of being un-navigable through the delta areas at certain times of year, definitely in deep summer. It’s definitely taking away spawning habitat, and habitat in general.

These are man-made issues partially. The salt and sand we’re putting on roads eventually makes its way into the streambeds and subsequently the river. I feel that there’s more that we can do to manage the sediment that shows up in these deltas, but it’s also a larger environmental issue because we are having this extreme flooding.

These rivers are the lifeblood of the lake. They are the lifeblood of the fisheries, the salmon fishery for sure. Without clear, clean water we won’t have a good fishery.

The fall salmon run happens later because we have longer hotter summers, and the cooler weather doesn’t hit until much later than it used to.

When I was a kid it was very rare to catch a largemouth bass around Chazy Landing. Now they are much more distributed throughout the lake than they used to be. The range of largemouth bass has changed because of fishing tournaments. [Warmer water temperatures] could be another reason for the change. Largemouth bass tolerate and like a warmer temperature, actually, so it could spread their range.

We see schools of the alewife out there. Sometimes we see a die-off washed up on the shoreline. It’s a boom and bust forage fish. The die-off seems to be a winter phenomenon, when the water gets really cold and ices over.

Silas Miller, age 35
Sailor and angler
Burlington, Vermont

Originally from Northville, Silas Miller has been fishing and sailing on Lake Champlain since he moved to Burlington, in 1995.

I’d say any spare moment I have, I try to be on the lake. I know the layout of the lake from sailing, but then also figuring out where the fish are at different times of year.

The thing I notice is that the storms of the last few years have really affected the lake heavily.

We couldn’t launch in the Shelburne Shipyard, where I sail out of, because the whole launching platform was under water [in 2011]. … Normally we launch in April; we didn’t launch until June. That was interesting.

The storms also seem to change the landscape of the rivers, the mouths of the rivers too. I notice tons of silt deposits everywhere on the lake that weren’t there a few years ago. Button Bay is a good example. I don’t understand how the silt ended up there, but it seems like there’s a foot or two of silt that is new in the past two years…. A lot of river deltas are extending into the lake and the lake levels seem to be lower because of it.

It was interesting this summer—I kept hearing people say, ‘The lake is lower than I’ve ever seen it in my life.’ I take that kind of thing with a grain of salt and I go and look at the data. People think it’s the lowest it’s ever been, but it’s just the lowest it’s been in five years. Recent memory is changing. I don’t know if it’s a combination of silt causing the lake to seem shallower last summer, or if it’s just the mindset because there’s been so much flooding and it’s been so deep for so long that people have had a shift in their mentality.

With sailing, the bigger impact of the storms is debris. If we are sailing along at 12 or 13 knots, if there’s been a storm, someone has to be on watch to look out for logs or things like that. If we hit something it could easily shear the keel and cause us to go over.

Algae blooms started early [in 2012] and went late. I was sailing late Oct­ober and there was a huge algae patch right in Shelburne Bay. Usually the blooms seem like they disperse, but this was actually a kind of algae that I hadn’t seen before. This bloom was probably 30 by 60 yards.

Mary Thill contributed research and interviews to this article. Curt Stager and Mary Thill are authors of the 2010 Nature Conservancy report, “Climate Change in the Champlain Basin: What natural resource managers can expect and do.” Stager is a professor of natural sciences at Paul Smith’s College, in Paul Smiths. Thill is a Saranac Lake–based freelance writer.

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