Led by paleoclimatologist 
 
Ulf Büntgen, researchers 
 
at Switzerland's Federal 
 
Research Institute 
 
for Forest, Snow 
 
and Landscape studied 
 
over 9,000 samples of 
 
tree ring data to create 
 
a 2,500-year history 
 
of European 
 
climate fluctuations. 
 
Comparing these to 
 
major historical events, 
 
the scientists determined 
 
a link between 
 
climate and society. 
 
They found, for instance, 
 
that the abundant crops 
 
nourished by wet and 
 
warm summers helped 
 
support prosperity 
 
during Roman and 
 
later in European 
 
Medieval times, 
 
and that the fall of the 
 
Western Roman Empire 
 
occurred during a period 
 
of drought and increased 
 
climate variability, which 
 
would have adversely 
 
affected food supplies. 
 
In another example, 
 
combined cold and 
 
wetter summers around 
 
1300 coincided with 
 
plague and famine that 
 
led to the loss of nearly 
 
half of Europe's 
 
population within
 
the next 50 years. 
 
The researchers concluded 
 
that climate change 
 
events which positively 
 
or negatively affected 
 
agricultural production 
 
amplified political, 
 
social and economic 
 
situations in the past, and 
 
may have implications 
 
for our modern era. 
 
Dr. Büntgen and colleagues
 
at the Swiss Federal 
 
Institute for Forest, 
 
Snow and Landscape, 
 
we appreciate your 
 
comprehensive analysis 
 
that shows the connection 
 
between physical 
 
and social events. 
 
May such revealing 
 
comparisons remind us to 
 
strive ever more urgently 
 
for lives of balance and 
 
harmony with nature.
 
As during an October 
 
2009 videoconference 
 
in Indonesia, 
 
Supreme Master Ching Hai 
 
has often discussed 
 
the importance 
 
of the moral aspect that 
 
determines a civilization's 
 
sustainability.
 
Supreme Master Ching Hai : If we have 
 
the spiritual eye, 
 
we will find that 
 
past civilizations, 
 
both on Earth and 
 
other planets, sometimes 
 
developed too quickly in 
 
the technological sense. 
 
But the spiritual 
 
development, 
 
their store of love, 
 
was low or empty. 
 
We see the pattern is that 
 
no society can last long 
 
if they refuse to 
 
sustain the lives of 
 
their own members and 
 
fellow beings; I mean, 
 
including all the beings, 
 
like animals and trees. 
 
Or, if they destroy the 
 
environment they live in, 
 
then that society 
 
cannot live long. 
 
The real problem is 
 
our meat consumption, 
 
the tendency of 
 
mass killing that we have 
 
made a part of our lives 
 
 
It is not normal. 
We cannot earn a living 
 
or sustain a living 
 
by death. 
 
Now, if we, 
 
the human race, develop 
 
as a vegan society, 
 
and better yet, 
 
a spiritual vegan society, 
 
there will be no limit to 
 
our material development. 
 
Because then, 
 
we will have the wisdom 
 
and the love to propel us 
 
on a balanced, straight 
 
course for the future, 
 
bright future, 
 
for our planet 
 
and our children. 
http://news.sciencemag.org/sciencenow/2011/01/fall-of-rome-recorded-in-trees.html?rss=1
 , 
http://voices.washingtonpost.com/postpartisan/2011/01/does_climate_change_explain_th.html,
 
http://www.swissinfo.ch/eng/science_technology/Scientists_link_bad_weather_to_historical_lows.html?cid=29224702