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Europe Inundated by Snow Down to Greece & Harvard Study Shows Oceans Are Getting Colder

This winter is once again extremely brutal in Europe. Extremely heavy snow has fallen as far south as Greece in the range of even 3 to 5 feet in various places. This is the third year of extreme cold in Europe which has been fueling more resentment about global warming taxes. Once again, Europe has been thrown into economic chaos for much of the region is not able to cope with snow lacking the historical experience.

Meanwhile, scientists have revealed that the oceans are still getting colder at deeper levels in a slow-moving trend that was set in motion by the last Little Ice Age. The idea that the oceans have been retaining the heat so that is why the planet has not warmed up as forecast 30 years ago flies in the face of those ideas as well.

The end of the Little Ice Age

The end of the Little Ice Age

The Little Ice Age (LIA) was a recent and significant climate perturbation that may still be affecting the Earth’s climate, but nobody knows what caused it. In this post I look into the question of why it ended when it did, concentrating on the European Alps, without greatly advancing the state of knowledge. I find that the LIA didn’t end because of increasing temperatures, decreasing precipitation or fewer volcanic eruptions. One possible contributor is a trend reversal in the Atlantic Multidecadal Oscillation; another is an increase in solar radiation, but in neither case is the evidence compelling. There is evidence to suggest that the ongoing phase of glacier retreat and sea level rise is largely a result of a “natural recovery” from the LIA, but no causative mechanism for this has been identified either.

The Little Ice Age (LIA) was a period of lower global temperatures defined by temperature reconstructions based mostly on tree ring proxies. Figure 1 shows the results of fifteen such reconstructions for the Northern Hemisphere with three instrumental records added after 1900 (data from NOAA/NCDC). The period of lower temperatures between about 1450 and 1900 roughly defines the LIA, but the high level of scatter (cunningly muted by plotting the more erratic reconstructions in lighter shades) makes it impossible to pick exact start and stop dates:

Figure 1: Northern Hemisphere temperature reconstructions over the last 2,000 years

Because of the problems with temperature reconstructions this post concentrates on the European Alps, where long-term instrumental records – some going back to the early 1700s – provide information on temperature and precipitation changes around the time the LIA came to an end. Another reason for concentrating on the Alps is that almost half of the world’s glaciers that have long-term monitoring data are located there.

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Scientists: Weak Ocean Circulation Could Signify Incoming Mini Ice Age

Scientists: Weak Ocean Circulation Could Signify Incoming Mini Ice Age

A weak circulation of ocean waters in the North Atlantic could signify that a mini ice age is just around the corner.  Scientists have discovered the weakening currents look similar to those that happened right before the Little Ice Age, a cold spell observed between about 1600 and 1850 AD.

During the Little Ice Age, the Baltic Sea, along with many of the lakes and rivers in Europe froze over. And new and recent studies are showing that the currents in the North Atlantic ocean are at their lowest in 1,500 years.  Scientists are about to blame a mini ice age on global warming climate change.

Researchers studied the Atlantic Meridional Overturning Circulation (AMOC), the branch of the North Atlantic circulation that brings warm surface water toward the Arctic and cold deep water toward the equator.

The research, co-led by Dr. Christelle Not and Dr. Benoit Thibodeau from the Department of Earth Sciences and the Swire Institute of Marine Science, The University of Hong Kong, is interpreted to be a direct consequence of global warming and associated melt of the Greenland Ice-Sheet.

Slower circulation in the North Atlantic can yield profound change on both the North American and European climate but also on the African and Asian summer monsoon rainfall. –The Daily Mail

“The discovery of this new record of AMOC will enhance our understanding of its drivers and ultimately help us better comprehend potential near-future change under global warming,” said Dr. Thibodeau.  “While we could ground-truth our temperature reconstruction for the 20th century against instrumental measurement it is not possible to do so for the Little Ice Age period, added Not. “Therefore, we need to conduct more analysis to consolidate this hypothesis.”

This weakening in the current is still vigorously debated because of the scarcity of long-term record of the AMOC.

Bond Cycles and the Role of The Sun in Shaping Climate

Bond Cycles and the Role of The Sun in Shaping Climate

Bond cycles are defined by petrological tracers from core samples in the N Atlantic that link to the pattern of drift ice distribution. They provide a record of shifting ocean currents and winds, in particular periodic weakening of the North Atlantic current and strengthening of the Labrador current. These cycles shape what we perceive as climate change in the circum North Atlantic realm, for example the Little Ice Age and Medieval Warm Period. They leave a small mark on global average temperatures that are difficult to resolve in the proxy temperature records

Bond Cycles correlate with cosmogenic 10Be suggesting that variations in solar and terrestrial magnetic field strength somehow link to changes in atmospheric circulation and ocean currents. My favoured explanation is changes in solar spectrum that accompany changes in the magnetic field.

With tens of thousands of papers published in climate science, it is possible to pick any 50 and come up with almost whatever narrative one wants. In this post I focus on evidence from ice rafted debris (IRD) dispersed in the N Atlantic from drift ice as presented by Bond et al 2001 [1]. I like the data because it is coherent with what is known about historic climate change in the N Atlantic realm (Figure 3).

Bond Data

Glaciers entrain rocks and rock fragments from the bedrock across which they grind and when they enter the sea to become icebergs and begin to slowly melt this detritus rains down to the sea bed (see inset photo up top). This ice rafted debris (IRD) can tell us something about where the icebergs came from. If the fragments are of granite or schist then this does not tell us anything specific about the source since granite and schist is common in many bedrock areas. But if the fragments are of volcanic glass, then they can only come from Iceland in the North Atlantic realm.

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