The range of instrumentation used to observe and measure climate is truly amazing.
The climate of a particular region is determined through analysis of Climatological variables in a region over a period of 30-years or greater.
Temperature (maximum, minimum, lower ground and soil) Wind speed Relative humidity Rainfall Atmospheric pressure Sunshine hours
Solar Activity can influence climate, primarily through changes in the intensity of solar radiation.
Volcanic Eruptions, like solar radiation, can alter climate due to the aerosols that are emitted into the atmosphere and alter climate patterns.
Precipitation (rainfall, snowfall etc) offers another indicator of relative climate variation and may include humidity or water balance, and water quality.
Biomass and vegetation patterns may be discerned in a variety of ways and provide evidence of how ecosystems change to adapt to climate change.
Chemical composition of air or water can be measured by tracking levels of greenhouse gases such as carbon dioxide and methane, and measuring ratios of oxygen isotopes. Research indicates a strong correlation between the percent of carbon dioxide in the atmosphere and the Earth’s mean temperature.
Sea Level measurements reflect changes in shoreline and usually relate to the degree of ice coverage in high latitudes and elevations.
Temperature : When measuring climate change this is a primary and can be measured or reconstructed for the Earth’s surface, and sea surface temperature (SST).