notorious

1 - Accurate data on the burden of infectious diseases in China are notoriously difficult to obtain.

2 - The US presidential election of 1800 was notorious on account of the unforeseen constitutional problems it presented.

3 - Cholesterol is notorious as a possible factor in heart disease, yet it is essential for the functioning of all our cells.

4 - Weather patterns are notoriously complex, which is why they are so hard to predict.

5 - In the history of public opinion research, no pot has ever gained so much notoriety as that conducted in 1936 by Literary Digest Magazine.