WHERE WE ARE GOING
Many people in Alaska the last few months have been wondering if global warming has stopped. Here in South-Central AK, Anchorage had it's 3rd coldest April since records began at the airport location in 1940, as well as abundant snowfall, making for prime nordic skiing. And most areas across the state had similar conditions. May continued in this vein. On the 17th, it was snowing right here at the Chugach Front Research Centre, and we picked up about 15 cm! (while our research-assistant Kluane was getting his birthday steak, he just turned 3, all grown up now!). In fact, it was the second-latest measurable snowfall in Anchorage, since 1940.
In the back-country about 10 km into the Chugach mtns., from its western front, snow conditions here just at 700 metres (2300 ft) in mid May were looking much like they would in March, with excellent packed powder and very little melt.
But, as you can see from this global surface temperature anomaly plot for the month of April 2013, although most of Alaska, and south through much of Canada into the central US was below-average, much of Siberia experienced above-average temperatures of about the same magnitude of departure from the means.
This extended cold period in Alaska makes sense to us, because as we have mentioned previously, the northern hemisphere jet stream seems to be slowing down, related to the loss of Arctic sea ice cover and decreased temperature gradients from the Equator northward.
And if the area you are in just happens to be stuck under a stationary low pressure trough in the jet stream, then cooler/wetter conditions will occur for an extended period. Warmer and drier if your area is stuck under a ridge ahead of or behind such a trough, as has been occurring in Siberia recently.
Latest research is also showing the melting conditions that occurred in Greenland last year, will likely become the norm in the next few decades. Which is not good news for sea-level rise scenarios.
As you probably know, globally-averaged atmospheric CO2 concentrations have reached 400 ppm recently, up from about 280 ppm 150 years ago, before the bulk of the "industrial revolution" and large-scale fossil fuel combustion. Well, as it turns out, there have been periods in the "relatively" recent geologic past where atmospheric concentrations have been that high, or even higher. From naturally-occurring volcanic activity, it is thought. And using various "proxy" methods of reconstructing temperatures from fossil data, it turns out that temperatures in the Arctic were as much as 5-10C warmer (9-18 deg F) on average, than they are currently (and global sea levels were 10-30 metres higher!). But what does that mean, as far as climatic conditions, and the ecosystems in the Arctic, what were they like during those times?
Fortunately, more light is being shed on that thanks to research on-going in northern Siberia at Lake El'gygytgyn, which was never scoured away by ice sheets during the ice ages of the past several hundred thousand years. So there are actually pollen traces in sediments dating from 2.2 to 3.6 mya, providing a fascinating glimpse of what conditions were like there in a currently very cold, treeless Arctic environment. Give this article a read, we're putting in some comments with it, and also afterward we'll discuss in more detail what we think may occur here in Alaska.
http://www.sciencedaily.com/releases/2013/05/130509142048.htm
Ice-Free Arctic May Be in Our Future, International Researchers Say
May 9, 2013 — Analyses of the longest continental sediment core ever collected in the Arctic, recently completed by an international team led by Julie Brigham-Grette of the University of Massachusetts Amherst, provide "absolutely new knowledge" of Arctic climate from 2.2 to 3.6 million years ago.
"While existing geologic records from the Arctic contain important hints about this time period, what we are presenting is the most continuous archive of information about past climate change from the entire Arctic borderlands. As if reading a detective novel, we can go back in time and reconstruct how the Arctic evolved with only a few pages missing here and there," says Brigham-Grette.
Results of analyses that provide "an exceptional window into environmental dynamics" never before possible were published this week in Science and have "major implications for understanding how the Arctic transitioned from a forested landscape without ice sheets to the ice- and snow-covered land we know today," she adds.
Their data come from analyzing sediment cores collected in the winter of 2009 from ice-covered Lake El'gygytgyn, the oldest deep lake in the northeast Russian Arctic, located 100 km north of the Arctic Circle. "Lake E" was formed 3.6 million years ago when a meteorite, perhaps a kilometer in diameter, hit the Earth and blasted out an 11-mile (18 km) wide crater. It has been collecting sediment layers ever since. Luckily for geoscientists, it lies in one of the few Arctic areas not eroded by continental ice sheets during ice ages, so a thick, continuous sediment record was left remarkably undisturbed. Cores from Lake E reach back in geologic time nearly 25 times farther than Greenland ice cores that span only the past 140,000 years. [there are no lakes like this in Alaska, that could provide that long of a record, eds.. ]
"One of our major findings is that the Arctic was very warm in the middle Pliocene and Early Pleistocene [~ 3.6 to 2.2 million years ago] when others have suggested atmospheric CO2 was not much higher than levels we see today. This could tell us where we are going in the near future. In other words, the Earth system response to small changes in carbon dioxide is bigger than suggested by earlier climate models," the authors state.
Important to the story are the fossil pollen found in the core, including Douglas fir and hemlock. These allow the reconstruction of vegetation around the lake in the past, which in turn paints a picture of past temperatures and precipitation. [the fact that Douglas fir and hemlock trees were growing in this now-frigid treeless Arctic environment, must have meant that conditions were similar to those in the US states of Washington, Oregon, northern Idaho, and western Montana, where these trees are prevalent now. Here is a photo we took in 9/2010, below, near Mt. Adams, WA showing the 3740m volcano (tree line is around 2100 metres) with it's lush forests of Douglas fir, western red-cedar, hemlock, and grand fir on it's lower slopes, contrast that with the currently bare treeless slopes around Lake E. eds...]
Another significant finding is documentation of sustained warmth in the Middle Pliocene, with summer temperatures of about 59 to 61 degrees F [15 to 16 degrees C], about 14.4 degrees F [8 degrees C] warmer than today, and regional precipitation three times higher. "We show that this exceptional warmth well north of the Arctic Circle occurred throughout both warm and cold orbital cycles and coincides with a long interval of 1.2 million years when other researchers have shown the West Antarctic Ice Sheet did not exist," Brigham-Grette notes. Hence both poles share some common history, but the pace of change differed.
Her co-authors, Martin Melles of the University of Cologne and Pavel Minyuk of Russia's Northeast Interdisciplinary Scientific Research Institute, Magadan, led research teams on the project. Robert DeConto, also at UMass Amherst, led climate modeling efforts. These data were compared with ecosystem reconstructions performed by collaborators at universities of Berlin and Cologne.
The Lake E cores provide a terrestrial perspective on the stepped pacing of several portions of the climate system through the transition from a warm, forested Arctic to the first occurrence of land ice, Brigham-Grette says, and the eventual onset of major glacial/interglacial cycles. "It is very impressive that summer temperatures during warm intervals even as late as 2.2 million years ago were always warmer than in our pre-Industrial reconstructions."
Minyuk notes that they also observed a major drop in Arctic precipitation at around the same time large Northern Hemispheric ice sheets first expanded and ocean conditions changed in the North Pacific. This has major implications for understanding what drove the onset of the ice ages.
The sediment core also reveals that even during the first major "cold snap" to show up in the record 3.3 Million years ago, temperatures in the western Arctic were similar to recent averages of the past 12,000 years. "Most importantly, conditions were not 'glacial,' raising new questions as to the timing of the first appearance of ice sheets in the Northern Hemisphere," the authors add.
This week's paper is the second article published in Science by these authors using data from the Lake E project. Their first, in July 2012, covered the period from the present to 2.8 million years ago, while the current work addresses the record from 2.2 to 3.6 million years ago. Melles says, "This latest paper completes our goal of providing an overview of new knowledge of the evolution of Arctic change across the western borderlands back to 3.6 million years and places this record into a global context with comparisons to records in the Pacific, the Atlantic and Antarctica."
The new Lake E paleoclimate reconstructions and climate modeling are consistent with estimates made by other research groups that support the idea that Earth's climate sensitivity to CO2 may well be higher than suggested by the 2007 report of the Intergovernmental Panel on Climate Change.
It really is quite amazing to think that it was so much milder and humid during that time in Northern Siberia, at the latitude of 68N. For hemlock and Douglas fir trees to be able to grow there, would have meant that winter temperatures must have rarely, if ever, dropped below -40C, and probably stayed between +5C and -30C most of the time (41F to -22F). Contrast that with Yakutsk, Siberia, further south at the latitude of 62N. Until relatively recently, the average high/low temperature for January in that city was -40C/-48C (-39F/-57F)!
The fact that there are still no trees growing around Lake E also means that average summer daytime high temperatures are probably only 10-13C (50-56F), whilst the research is showing that temperatures there 2.2-3.6 mya were 8-10C warmer. Meaning that summer daytime temperatures there were probably routinely 20-25C (68-77F). We think that for these mild of conditions to have been able to occur there, the Arctic ocean probably stayed unfrozen through the winter, at least along the southern continental margins. Because currently, when there is a solid Arctic sea ice cover from roughly late October through April, this ice sheet acts as a continental land mass in the radiative sense. That is, radiative heat loss is very strong during clear weather during long polar nights, allowing temperatures to drop to -30C to -50C. Under open-water conditions in winter, the northern coastlines of Eurasia and North America would have been much warmer. _svg.png)
The Eurasian land mass is much bigger than North America, and contains more land in the latitudes of 40N-70N. Thus in winter, when the northern hemisphere is tilted away from the sun, the Eurasian land mass cools much more strongly than does North America. Wintertime temperatures in places like China, Japan, Korea, and southern Siberia, are much colder than areas in eastern North America at similar latitudes.
Thus, we would expect that Alaska would experience somewhat warmer temperatures in winter than Lake E, once the climate system "catches up" to our current 400 ppm CO2 (and it's likely to reach at least 500-550 ppm by 2080 under current emissions scenarios). Below are the current average maximum temperatures for Yakutsk, Siberia, which is at 62N. Summer highs there are warmer than Lake E, because it is further south, and much further removed from the Arctic coast.
As you can see, from this photo of Avalanche Creek, in Glacier National Park, Montana, it is quite moist and lush there during the summer, yet a real winter snowpack occurs, and temperatures can drop to -30C (-22F) occasionally during winter. Below are monthly mean temperatures and precipitation data for West Glacier, Montana. Period of Record : 10/1/1949 to 3/24/2013
http://www.wrcc.dri.edu/cgi-bin/cliMAIN.pl?mt8809
Note the relatively mild winter-time temperature averages, and the 30 inch annual precipitation (76cm). Thus, in our estimation, climatic conditions around Lake E., at 68N, must have been similar to this 2.2-3.6 mya, when the atmospheric CO2 concentration was around 400 ppm. Siberia would still experience, even under the 400 ppm CO2 scenario, the coldest winter-time temperatures in the Northern Hemisphere. But the current coldest climate that still allows for the growth of Douglas fir/hemlock trees is in the favoured upslope areas of southern British Columbia, Canada, and northern Idaho/western Montana, USA. That is a huge difference between the frigid Arctic climate Lake E still experiences (but that is changing). Annual precipitation values in Arctic areas like Lake E., are currently only around 5-10 inches (11-25cm). Douglas fir and hemlock trees generally only grow in climates that receive at least 18-20 inches of precipitation annually (hemlocks are an even moister species, and usually require 25-30 inches or more).
Now, since Alaska is surrounded by the Arctic Ocean, Bering Sea, and Pacific Ocean on three of it's sides, under the warmer climate scenario as found 2.2-3.6 mya, open water conditions over the Arctic Ocean and Bering Sea (except perhaps briefly in the depths of winter, a thin transitory ice cover might form), would likely lead to even milder conditions. 
Under the warmer climate scenario, a good current analogue for Fairbanks, in the interior, which has very cold winters (but not as cold as Siberia!) might be The Dalles, Oregon. Fairbanks lies at only 100 metres elevation, hundreds of km inland, and so is fairly dry, receiving on average only 10-12 in. of precipitation (30.5 cm) annually. Here are climate data for The Dalles, Oregon. Period of Record : 1/ 1/1893 to 2/28/2013
http://www.wrcc.dri.edu/cgi-bin/cliMAIN.pl?or8407
The Dalles is 150 km inland from the Pacific Ocean, and lies in the "rain-shadow" of the Cascade Mountains, and hence is fairly dry. And heading further inland from there, annual precipitation drops even further to 7-9 inches, at the lowest elevations in central Washington, along the Columbia River. Here are the current climate data for Fairbanks, take a moment to mull that over. When the climate system "catches up" to our current 400 ppm CO2, and then even higher levels after that, eventually the Alaska Interior will likely see conditions more like those from The Dalles, Oregon, or even warmer!
http://www.wrcc.dri.edu/cgi-bin/cliMAIN.pl?ak2968
This also means that the current boreal forest cover throughout Interior Alaska of black/white spruce, aspen, birch, balsam-poplar, and willows, would be unable to grow under these much warmer/drier conditions. Dry valley areas like Fairbanks would transition to just having a grass/sagebrush biome, perhaps with scattered areas of aspen and ponderosa pine on cooler, north-facing slopes.
Now what about Anchorage, the biggest city here in Alaska, where over 50% of the people in the state live. What can we expect under the 400ppm CO2 warming scenario here? Let's look at the current data:
http://www.wrcc.dri.edu/cgi-bin/cliMAIN.pl?ak0285
These numbers are for the Anchorage airport, which is somewhat milder in winter, and cooler in summer, than the Chugach Front Research Centre, which lies at the foot of the Chugach mountains, 15 km further inland. Note how relatively dry it is in summer here, the Chugach mountains block precipitation that tries to move in from the south through east and northeast when there are low pressure systems in the Gulf of Alaska. Which occur there very frequently.
What we think could be a good representation of climate conditions for Anchorage under the 400ppm CO2 level scenario would be those currently experienced in Port Townsend, WA.
Summer-time temperatures there are fairly cool due to the proximity of the cool waters of the Strait of Juan de Fuca/Puget Sound, yet the annual precipitation is only 18.7 inches (47.5cm), due to the shadowing influence of the Olympic mountains, which blocks precipitation from the southwest through south. Note how infrequent snowfall is there, and that monthly mean snow depths in the coldest months are still zero. Forest cover around Anchorage would likely transition from the current boreal forest species of birch/aspen and white/black spruce, to the Douglas fir/ponderosa pine species found in drier coastal areas around Puget Sound, WA.
What about around the Gulf of Alaska, where milder maritime conditions already allow thick "rain-forest" type vegetative growth to occur? Say, just 100 km south of Anchorage, in Seward, what might it be like there under the warmer scenario? Following are the current monthly averages for Seward.
We think a good analogue for Seward under the 400ppm CO2 warming scenario would be the conditions currently found along the Washington and Oregon coastlines, cool and moist, but lacking any but the most transitory winter snowfalls/snowcover, and rarely experiencing winter temperatures below -10C (14F). This climate allows for the rapid growth of the temperate rainforest cover of Douglas fir, hemlock, western red-cedar, sitka spruce, and grand fir. Some of these can reach 100 metres in height with 5-10m trunk diameters at their bases, in favoured areas. As we see in this photo, which your lead editor took last October, just north of Newport, Oregon, about 2km inland in a 300m deep canyon.
Here are the monthly averages for Newport, Oregon. Note the very mild winter temperatures, but still cool summers, due to the proximity of the cold waters of the Pacific Ocean.
http://www.wrcc.dri.edu/cgi-bin/cliMAIN.pl?or6032
In this case, the current thick vegetative cover found around the Gulf of Alaska coastline of Sitka Spruce and hemlock, would slowly transition to that currently found further south in Washington and Oregon. With Douglas fir, western red-cedar, and grand fir mixing in, and becoming larger, with longer growing seasons, but still-abundant moisture.
Now, in all these scenarios we have presented you, with climate data that could represent areas in Alaska under a future 400ppm CO2 warming, nowhere have we mentioned how long it will take for these warmer conditions to be reached. That's because this is a great unknown. Obviously, the longer this takes the better, to allow the ecosystems and humanity in general to adapt. As we mentioned previously, over the past 60 years, roughly, temperatures have warmed 3F (1.7C) on the average in Alaska.
Temperatures will continue to warm at least another 4-8C, or more, to "catch-up" with atmospheric CO2 levels of 450-550 ppm, which hopefully will be as high as they reach, before changes in our political/economic systems allows societies to transition to renewable, non-greenhouse gas emitting power sources for energy/transportation needs (if that is even possible before dire collapse scenarios occur).
How long will this be? We think it will be 50-80 years, at the minimum, before temperatures in Alaska, and throughout the Arctic, reach these levels. Which is a very short time geologically speaking, and would create large stresses on all the ecosystems (and already are) in the Arctic.
We also expect that the current trends we are seeing in our climatic conditions in Alaska will continue, and amplify in frequency and strength, as warming increases. Which will have unfortunate effects for most of us in Alaska.
Likewise, the snowy winters we have seen recently in south-central Alaska, will transition to increasingly warmer and wetter ones, as the jet stream continues to move further north with the increasing warming.
We do hope that climate-change modeling can help to refine timelines for the coming warming, not just here in the Arctic, but throughout the World. To help societies adjust to the coming changes, which are a matter of when, not if. For if climatic conditions in the Arctic under a 400 ppm CO2 concentration were similar to those currently in the northwestern lower 48 states, what do you think conditions would be like in California, or Arizona, let's say, when 500 ppm CO2 is reached, and then the climate system "catches up"?
WHERE WE HAVE BEEN
For a break from more serious information, we thought we'd provide you with a few pictures from our activities of the past month. During the latter part of April and into early May, your lead editor flew south to balmy San Diego, CA, where I grew up. And where my sister and brother still live. Always an interesting place to visit, with a large variety of experiences possible.
The immediate coastline, especially from La Jolla north to Del Mar, is our favourite area of San Diego, and where I always venture to first, and spend the most time.
Great opportunities for hiking, running, swimming, surfing, scuba diving, and kayaking can be found here, and in which we liberally partake. Kayaking around La Jolla shores beach and to La Jolla Cove, allows you to get up close to the playful sea lions which have greatly increased their numbers in that area, since I was a child in the late 1970s/early 1980s.
They sure are fun to be around, with their bellowing and playful antics, as long as you don't get too close and interfere in their activities.
Whilst on a short side trip north to the appalling dystopian urban agglomeration of the Los Angeles/Hollywood area, our great friend Erik Skye and I were able to do a nice hike in the Hollywood hills, and look back upon it absent it's usual thick air pollution.
I am always on the lookout for representative creatures of whatever ecosystem I happen to be in. And so I was very happy to see this young rattlesnake on the trail, near the top of the Hollywood hills.
These young ones can be even more dangerous than mature rattlesnakes, as they are unable to control the amount of venoum they release during a bite. Hence, I stayed at least a metre away from it.
My favourite hike of the San Diego trip was in Anza-Borrego Desert State Park, 110 km to the east, in Palm Canyon.
Both on this hike, and in a previous one in 2012, I have seen the shy, endangered desert bighorn sheep. Always a special experience to be close among these tough, but graceful and gentle creatures. To see them nibbling on the desert vegetation, and hear the clacking of their hooves, as they clamber up the steep, rocky canyon walls.
Other denizens of this beautiful remote desert canyon were out for our enjoyment, though not knowing if they were venomous, made us keep our distance.
This Chuckwalla though, we knew not to be venomous, it was trying to elude us before we could get a good photo.
During this time, my left leg was becoming increasingly stiff and sore, due to the titanium screws and plate that were installed last October. Keeping me from running, and causing my hiking to be slower and usually painful. This metal hardware was necessary though to re-build my tibia, which was broken in the running accident that I experienced last fall. 
Surgery had already been scheduled for the 15th of this month to remove it, as it had served it's purpose, allowing me to walk again, and in it's absence, hopefully to run again. So I had to spend a frantic time after returning from my San Diego trip to prepare for this and a return to temporary disability.
The operation to remove the hardware went well, so far with no complications, though the leg is still exceedingly swollen and stiff. Of course, it has only been 8 days after a 15cm incision, and 5 holes (3 for arthroscopic investigation around the knee, which found good conditions, thankfully) were done. Your lead editor hopes to be able to run with the rest of the APR staff again by August. Cheers.
