Atmospheric sciences and radiant energy. In contrast to meteorology, which studies short term weather systems lasting up to a few weeks, climatology studies the frequency and trends of those systems. It studies the periodicity of weather events over years to millennia, as well as changes in long-term average weather patterns, in relation to atmospheric conditions. Climatologists, those who practice climatology, study both the nature of climates – local, regional or global – and the natural or human-induced factors that cause climates to change. Climatology considers the past and can help predict future climate change. Phenomena of climatological interest include the atmospheric boundary
Long-term effects of alcohol consumption observed in alcohol users classified as occasional as well as regular light, moderate, and heavy consumers. Another large study of 4465 subjects in India also confirmed the possible harm of alcohol consumption on coronary risk in men. Compared to lifetime abstainers, alcohol users had higher blood sugar (2 mg/dl), blood pressure (2 mm Hg) levels, and the HDL-C levels (2 mg/dl) and significantly higher tobacco use (63% vs. 21%). Many countries collect statistics on alcohol-related deaths. While some categories relate to short-term effects, such as accidents, many relate to long-term effects of alcohol. One study claims that "excessive alcohol consumption