The little ice age happened when we were furiously burning coal, a fossil fuel.
funny you should mention that along with natural causes we have this
http://news.bbc.co.uk/1/hi/sci/tech/4755328.stm
"Europe's "Little Ice Age" may have been triggered by the 14th Century Black Death plague, according to a new study."
http://stephenschneider.stanford.edu/Publications/PDF_Papers/Ruddiman2003.pdf
"A wide array of archeological, cultural, historical and geologic evidence points
to viable explanations tied to anthropogenic changes resulting from early agriculture in Eurasia,
including the start of forest clearance by 8000 years ago and of rice irrigation by 5000 years ago. In
recent millennia, the estimated warming caused by these early gas emissions reached a global-mean
value of ∼0.8 ◦C and roughly 2 ◦C at high latitudes, large enough to have stopped a glaciation of
northeastern Canada predicted by two kinds of climatic models. CO2 oscillations of ∼10 ppm in the
last 1000 years are too large to be explained by external (solar-volcanic) forcing, but they can be
explained by outbreaks of bubonic plague that caused historically documented farm abandonment
in western Eurasia. Forest regrowth on abandoned farms sequestered enough carbon to account for
the observed CO2 decreases. Plague-driven CO2 changes were also a significant causal factor in
temperature changes during the Little Ice Age (13001900 AD)."
http://www.sciencenews.org/view/generic/id/335168/title/Columbus_arrival_linked_to_carbon_dioxide_drop
"The European conquest of the Americas decimated the people living there, leaving large areas of cleared land untended. Trees that filled in this territory pulled billions of tons of carbon dioxide from the atmosphere, Stanford University geochemist Richard Nevle reported October 11 at the Geological Society of America annual meeting. Such carbon dioxide removal could have diminished the heat-trapping capacity of the atmosphere and cooled the climate, Nevil and his colleagues have previously reported.
We have a massive reforestation event thats sequestering carbon
coincident with the European arrival, said Nevle."
