Russian scientists found traces of global warming in the Tibetan cedars

© Fotolia / mamahoohoobaОзеро AMCO-Yumco in TibetRussian scientists found traces of global warming in the Tibetan cedars© Fotolia / mamahoohooba

. Annual ring Tibetan cedars prompted Russian climatologists that global warming is beginning to affect the ecosystems in this part of China in the early 1980s, the press service of the Russian science Foundation.

«Modern methods for assessing the influence of climate on vegetation imperfect. Satellite remote observations cover only the last 35 years. To resolve the contradictions necessary set of ground-based data, which covers a much longer period,» says Vladimir Shishov, a climatologist from the Siberian Federal University in Krasnoyarsk.

The role of such indicator, as noted Shishov, perfect growth rings of trees that grew in one place for several centuries.
Trees and other vegetation are very sensitive to the slightest change in climate — the increase or decrease of temperature, solar radiation and other factors. All of these events affect the shape and thickness of the annual rings — layers of wood in the trunk, which is formed during the growing season. It is believed that the dark rings correspond to adverse environmental conditions, and the light is favorable.

Due to this, the ancient trees-centenarians represent a very detailed and accurate climate records, learning that, scientists will not only learn how changing temperature and precipitation, but also figure out when there is a supernova and other cosmic disasters, monitor the level of rare isotopes in the annual rings.

As blogged Shishov, his team was primarily interested in how changing the growth rate of trees in response to increases and decreases of average temperatures that have been associated with natural and anthropogenic climate change.

Tibet, like many other regions of the world, should be the first «victim» of global warming affecting mountain and polar regions is much stronger and faster than in temperate and tropical latitudes. For this reason, scientists have long been interested in whether there is in Tibet, the first traces of such changes and, if so, when they appeared.

With the support of the Chinese Academy of Sciences, Russian climatologists have measured the diameter of tree rings for hundreds of cedars that grew in 20 parts of Tibet in the past 55 years. They used these data to create a virtual analogue of the Tibetan forests and measure how varied the biomass growth rate from 1960 to 2014.

It turned out that before 1981, the Tibetan cedars started to grow in the spring and finished its growth in the fall around the same time, however, since then the situation has changed. Since 1982, the length of the vegetative period began to grow, expanding both from the spring and autumn. Overall, the cedars began to grow for six days earlier than in past historical periods, and the period of growth was prolonged for 10 days.

In the near future, scientists plan to conduct similar studies in other regions of the Northern hemisphere that will help Russian climate scientists a more complete picture of how the planet’s ecosystems respond to global warming.