**4. Discussion and conclusion**

154 Atmospheric Model Applications

The results revealed that, for July month, there exist a very strong, high significant positive correlation coefficient (+0.764) with a significant level more than 0.99 % between anomalies in surface air temperature and geopotential height over Russia through the period of study. In addition to that through , anomalies in surface air temperature has a significant negative correlation coefficient (-0.289) with a significant level of 0.95 % with NAO. Also, the results show that there is a strong significant positive correlation coefficient (+0.477) with a significant level of 0.975% between the anomalies of surface air temperature over Russia and

> Geopotential height at 500 hpa level over Russia

NAO -0.289 -0.064 1 +0.217 SOI +0.477 +0.573 +0.217 1

Table 2. Correlation coefficient matrix for Weather and climatic parameters over Russia and

For August month, there exist a strong, high significant positive correlation coefficient (+0.605) with a significant level more than 0.97 % between anomalies in surface air temperature and geopotential height over Russia through the period of study. In addition to that, anomalies in surface air temperature has a significant negative correlation coefficient (- 0.285) with a significant level of 0.95 % with NAO. Also, the results show that there is a strong significant positive correlation coefficient (+0.264) with a significant level of 0.90 % between the anomalies of surface air temperature over Russia and SOI as shown in Table(3).

> Geopotential height at 500 hpa level over Russia

NAO -0.285 -0.101 1 +0.018 SOI +0.264 +0.255 +0.0184 1

Table 3. Correlation coefficient matrix for weather and climatic parameters over Russia and

1 +0.605 -0.285 +0.264

+0.605 1 -0.101 +0.255

1 +0.764 -0.289 +0.477

+0.764 1 -0.06479 +0.573

NAO SOI

NAO SOI

SOI as shown in Table(2).

Correlation coefficient

Correlation coefficient

Weather and climatic parameters

Surface air temperature over

Geopotential height at 500 hpa level over

Russia

Russia

Surface air temperature over Russia

climatic indices NAO and SOI for July month

Surface air temperature over Russia

climatic indices NAO and SOI for August month

Weather and climatic parameters

Surface air temperature over

Geopotential height at 500 hpa level over

Russia

Russia

Abnormal hot and dry weather has hit Russian regions in the summer of 2010. Many Russians are suffering from the record-breaking heat and the worst drought in 40 years. Russia was not import grain this year despite drought wiping out a quarter of its crops. The present study the hot wave over Russia on summer 2010 are a result of extreme global atmospheric abnormal interaction between the southern hemisphere(represented by SOI) and the northern hemisphere (represented by NAO) through that season. Abnormal interaction between these two major climatic indices of pressure systems that controlling the atmospheric dynamic in the globe generates a unique blocking high over the northern hemisphere. This blocking high persisted for a long time over Russia about 80 days with anomalies in geopotential height more than +100 m in 500 hpa level. The long persistence of this episode is due to the long abnormal interaction between SOI and NAO through that summer. The blocking high over Russia associated with abnormal warming in the upper atmosphere and causing of very extreme heating in the surface. Hot waves over Russia are a results of the long persistence of the blocking high episode that existed from the abnormal atmospheric interactions in the globe. One can concluded that, extreme flow air currants in both hemispheres (represented in the extreme values of NAO and SOI)disturb the flow to be stationary and blocked the air current flow aloft over the northern hemisphere during summer 2010. The hot waves over Russia is a result from the extreme atmospheric climatic interaction between both hemispheres.
