Levac (2001) examined the Holocene history of Canada's Atlantic region using a high-resolution palynological record obtained from the Scotian Shelf.  This work revealed that sea surface temperatures in February and August were up to 5°C warmer than those of today from approximately 10,500 to 8,500 years ago.  They then declined for about the next 2,000 years, after which August temperatures remained similar to August temperatures of today, while February temperatures remained about 2°C warmer than today's normal.  Exceptions to these general conditions occurred at roughly 1000-year intervals, when periods of significantly colder temperatures prevailed, with the last 500 years of the record (which ends about 100 years ago) depicting a slight cooling of August temperatures.

Levac's work reveals that climate has changed significantly many times throughout the course of the last ten millennia in the area of Canada's Atlantic Provinces; and the vast majority of these changes have occurred independently of changes in atmospheric CO2 concentration.  During this period, it has been both warmer and colder than it is now - several times, in fact - and neither a future warming nor cooling would be anything unusual for this part of the globe.  Both types of transitions have occurred before, and both will likely occur again, independent of anything man may do, including the continued burning of prodigious quantities of fossil fuels.

Fallu et al. (2005) extracted a sediment core from a shrub-tundra lake in northern Quebec, which they analyzed for chironomid head capsules, diatoms and pollen that revealed "environmental changes in greater detail than previously attained in paleoecological studies from northern Quebec-Labrador."  After an initial increase in temperature that lasted from 6400 to 4900 cal. yr BP, a warm phase set in that lasted from 4900 to ca. 1500 cal. yr BP.  Then came what Fallu et al. call the "recent cooling," which lasted from "ca. 1500 cal. yr BP to modern time," during which interval they report that "lake water temperature apparently became increasingly unstable," in contradiction of climate-alarmist dogma that temperatures become more variable when it warms.  Also in contradiction of climate-model wisdom, they note that although their study was conducted at high sampling resolution, "it was impossible to discern any recent warming trend that could be related to anthropogenic activities," and in another place they simply state that "no recent warming trend was detected."

Moore et al. (2001) analyzed sediment cores from Donard Lake on Baffin Island to produce a 1240-year record of summer temperatures that averaged 2.9°C for the entire period from AD 750-1990.  Anomalously warm decades with temperatures as high as 4°C occurred around AD 1000 and 1100; and at the beginning of the 13th century, Donard Lake witnessed "one of the largest climatic transitions in over a millennium," as "average summer temperatures rose rapidly by nearly 2°C from AD 1195-1220, ending in the warmest decade in the record," with temperatures near 4.5°C.  This rapid warming of the 13th century was followed by a period of extended warmth that lasted until an abrupt cooling event occurred around AD 1375.  The following decade was one of the coldest in the record and represented the onset of the Little Ice Age on Baffin Island, which lasted for 400 years.

At the modern end of the record, a gradual warming trend occurred over the period 1800-1900, followed by a dramatic cooling event in 1900 that brought temperatures back to levels consistent with the Little Ice Age, which lasted until about 1950.  Temperatures then warmed during the 1950s and 1960s, but they have since trended downward toward cooler conditions.  In contradiction of model-inspired climatology, this study thus demonstrates the existence of both the Medieval Warm Period and Little Ice Age on Baffin Island; and it rebuffs the climate-alarmist claim that the latter part of the 20th century experienced a warming that was unprecedented over the past thousand years ... at least in this part of the world, which is, however, where CO2-induced global warming is supposed to be most strongly expressed.

Luckman and Wilson (2005) used new tree-ring data from the Columbia Icefield area of the Canadian Rockies to develop a significant update to a millennial temperature reconstruction published for this region in 1997.  The new update employed the increasingly-utilized regional curve standardization method, in an effort to capture a greater degree of low frequency variability (centennial to millennial scale) than reported in the initial study.  In addition, the new data set added over one hundred years to the chronology, which now covers the period 950-1994 and reveals that generally warmer conditions prevailed during the 11th and 12th centuries, between about 1350-1450 and from about 1875 through the end of the record.  The warmest reconstructed summer occurred in 1434 and was 0.23°C warmer than the next warmest summer that occurred in 1967.  Persistent cold conditions prevailed between 1200-1350, 1450-1550 and 1650-1850, with the 1690s being exceptionally cold (more than 0.4°C colder than other intervals).  The new Columbia Icefield record thus provides further evidence for natural climate fluctuations on centennial-to-millennial time scales and demonstrates, once again, that temperatures of the present era are no different from those observed during the Medieval Warm Period (11-12th centuries) or the Little Medieval Warm Period (1350-1450).  And since we know that atmospheric CO2 concentrations had nothing to do with the warm conditions of those earlier periods, they likely have nothing to do with the warm temperatures of the modern era.  In fact, Luckman and Wilson note that their temperature reconstruction "appears to indicate a reasonable response of local trees to large-scale forcing of climates, with reconstructed cool conditions comparing well with periods of known low solar activity," which is a nice way of saying that the sun is probably the main driver of these low frequency temperature trends.

Girardin et al. (2004) developed a 380-year reconstruction of the July monthly average of the Canadian Drought Code (CDC, a daily numerical rating of the average moisture content of deep soil organic layers in boreal conifer stands) from 16 well replicated tree-ring chronologies from the Abitibi Plains of eastern Canada just below James Bay.  In doing so, they discovered that "cross-continuous wavelet transformation analyses indicated coherency in the 8-16 and 17-32-year per cycle oscillation bands between the CDC reconstruction and the Pacific Decadal Oscillation prior to 1850," while "following 1850, the coherency shifted toward the North Atlantic Oscillation."  These results led them to suggest that "the end of [the] 'Little Ice Age' over the Abitibi Plains sector corresponded to a decrease in the North Pacific decadal forcing around the 1850s," and that "this event could have been followed by an inhibition of the Arctic air outflow and an incursion of more humid air masses from the subtropical Atlantic climate sector."

In support of this interpretation, Girardin et al. note that several paleo-climatoogical and paleo-ecological studies have suggested that "climate in eastern Canada started to change with the end of the 'Little Ice Age' (~1850)," citing the works of Tardif and Bergeron (1997, 1999), Bergeron (1998, 2000) and Bergeron et al. (2001), while further noting that Bergeron and Archambault (1993) and Hofgaard et al. (1999) have suggested that "the poleward retreat of the Arctic air mass starting at the end of the 'Little Ice Age' contributed to the incursion of moister air masses in eastern Canada."  This substantial group of reports clearly places the "beginning of the end" of the Little Ice Age in eastern Canada fully half a century before what is suggested by Mann et al.'s (1998, 1999) reconstruction of Northern Hemispheric temperature.  Hence, it represents an entire group of studies that testifies against the validity of that faulty temperature history, where the recovery warming from the global chill of the Little Ice Age does not begin until after 1910; but it supports the more realistic results of Esper et al. (2002), where Northern Hemispheric warming begins in the early to mid-1800s.

Based on an analysis of an ice core retrieved from a high elevation site on Mount Logan (Canada's highest mountain, located in the heavily-glaciated Saint Elias region of the Yukon on the western side of the country) plus shallow coring and snow-pit sampling, Moore et al. (2002) derived a snow accumulation record stretching from 1693 to 2000.  This history indicates, in their words, that "heavy snow accumulation at the site is associated with warmer tropospheric temperatures and higher geopotential heights over northwestern North America," and, hence, it suggests that their snow accumulation record is a proxy for near-surface air temperature over the past three centuries in this region, the first half of which shows no significant trend.  From 1850 onward, however, there is a positive trend, significant at the 95% confidence level, which appears to be associated with the Pacific North America pattern (Wallace and Gutzler, 1981; Barnston and Livezey, 1987) and the Pacific Decadal Oscillation (Zhang et al., 1997).  This important new data set thus casts still more doubt upon the IPCC-endorsed "hockey stick" temperature history of Mann et al. (1998, 1999), while at the same time supporting the more realistic record of Esper et al. (2002).

Focusing of the same topic, Majorowicz et al. (1999) derived proxy temperatures for the past three centuries from borehole temperature-depth logs obtained from ten sites scattered throughout southern Saskatchewan.  These histories indicate the existence of a relatively cool period over the initial third of their duration.  Then, from about 1820 to the ends of the records, temperatures rose between 2.5 and 3.0°C, suggesting to Majorowicz et al. that "almost half of the warming occurred prior to 1900, before the dramatic buildup of atmospheric greenhouse gases."  Their work in yet another part of Canada thus adds to the growing mountain of evidence that demonstrates the flawed nature of the Mann et al. temperature history of North America; and it also points to the reason why the IPCC is reluctant to disavow that "hockeystick" representation of temperature evolution: the true temperature history of North America is not compatible with the theory of greenhouse gas-induced global warming.

We complete our geographical tour of Canada by reviewing the findings of Futter (2003), who analyzed data on ice break-up dates and length of ice-free season for several lakes in Southern Ontario, but where only one lake had data extending back beyond 1910 (Lake Simcoe, to 1853).  Breaking its history into three comparable time intervals (1853-1899, 1900-1949, 1950-1995), Futter determined that "only the period from 1853-1899 showed a statistically significant trend indicative of warming temperatures in both the ice break up and ice free season series."  In fact, he reports that the data from 1900-1949 indicate a cooling trend, and that the data from 1950-1995 "show slight but not statistically significant evidence of warming."  Once again, therefore, and from yet another part of Canada, we see evidence of recovery warming from the Little Ice Age beginning somewhere in the mid-19th century, and only a slight non-significant warming over the last half of the 20th century, contradicting the temperature history of Mann et al. in about every way possible.

In conclusion, numerous studies conducted throughout Canada provide compelling evidence for a millennial-scale oscillation of climate that is likely solar-induced and responsible for producing medieval warmth that was comparable to, or even greater than, that of the present, as well as a post-Little Ice Age warming that began in the mid-1800s, the early stage of which was often more substantial than that of the late-20th century, all of which findings are at odds with the Northern Hemispheric temperature history of Mann et al., which is used by climate alarmists to support their claim that anthropogenic CO2 emissions are responsible for a post-1910 warming that in the late-20th century appears to have been unprecedented with respect to the prior two millennia.  Clearly, this faulty temperature history should long ago have been retired from the debate over greenhouse gas-induced global warming.  That the IPCC still clings to it can only be interpreted as a sign of extreme weakness in the other "evidence" they use to support their favorite theory, i.e., that much of the warming of the past century is human-induced, due primarily to anthropogenic CO2 emissions.  Real-world data soundly refute that contention.

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