This diploma thesis is dealing with comparison of relationships between climate characteristics and radial growth. We were dealing with growth response of trees in different conditions for its growth. The chronology is based on cores from Picea glauca and Picea mariana, which use to grow in the area northern high-latitude ecosystems and Picea abies, which use to grow in High Tatras, under the upper forest boundary. It is dealing with cases which occur at the edge of native azonal and zonal distribution of this plants. Cores of Picea glauca and Picea mariana were taken in 2015 from Canada at the boundary of Yukon Territory and the Northwest Territories. Cores of Picea abies, were taken from dying trees, which were attacked by bark beetle. Main point of this thesis was measurement of tree-rings, its cross-dating and standardization of tree-rings series. As a result there are growth indexes. From these indexes are for trees created residual chronology. In time span 1901-2015 It was created databases for 2 main climate characteristics- monthly precipitation and average monthly temperature. After 1980 was discovered clear temperature increasing from comparison of long-term average temperatures. Surmise was, that increasing of temperature is supporting ring widths yields, where is temperature considered as limiting factor. In case of Picea abies, is increasing of basal area confirmed. Canadian environment is specific for low temperature (average year temperature is -10,12 °C, during winter even -30 °C). Increasing of the temperature didn´t have significant influence on ring widths. Increasing of the temperature in this extreme conditions decline its tree growth, because drought has negative impact on tree growth. As we can see in the results, observation of climate changes is possible also through trees, because they are as a mirror of their growing condition. If there is some change of conditions, they react by change of growth. They also offer themselves as a source of information from previous times. We can also forecast future behaviour of trees and according that, adapt better forest management for production and stability of forest.