Question

Which of the following statements are correct ? 

1. A new study has found that changes in solar activity contributed no more than 10 per cent to global warming in the 20th century published in the journal Environmental Research Letters. 

2. It has been proposed that cosmic rays may have a role in cooling the earth by encouraging clouds to form, which subsequently reflect the sun’s rays back into space. 

3. Researchers found high correlation between cosmic rays and global temperatures occurring every 22 years. 

Select the answer from the codes given below- 

(a) 1 only 

(b) 1 and 2 only 

(c) 2 and 3 only 

(d) All of the above

Answer 1

Correct option: (b) 1 and 2 only

Explanation:

The Researchers found a small correlation between cosmic rays and global temperatures occurring every 22 years; however, the changing cosmic ray rate lagged behind the change in temperatures by between one and two years, suggesting that the cause might not be down to cosmic rays and cloud formation but might be due to the direct effects of the sun. By comparing the small oscillations in the cosmic ray rate, which were taken from data from two neutron monitors, and temperature with the overall trends in both since 1955, the research team found that less than 14 per cent of the global warming seen during this period could be attributable to solar activity.