A significant source of uncertainty in our global climate trend data is the locations where the data are collected.
Many meteorological stations are near cities which generate significant amounts of local heat.
Scientists try to compensate by comparing this data to data collected in rural areas, however, it is still a source of uncertainty in land-based temperature data. This is a summary of the cited web page. This evidence demonstrates the need for critical assessment of scientific data and theories dependent on that data. The KIE Group. All rights reserved.