Map climatic features as the long-term mean values (of atmospheric pressure, temperature, humidity, total precipitation, and so forth) to connect points with equal values of the feature in question—for example, isobars for pressure, isotherms for temperature, and isohyets for precipitation. Isoamplitudes are drawn on maps of amplitudes (for example, annual amplitudes of air temperature—that is, the differences between the mean temperatures of the warmest and coldest month). Isanomals are drawn on maps of anomalies (for example, deviations of the mean temperature of each place from the mean temperature of the entire latitudinal zone). Isolines of frequency are drawn on maps showing
Desorption atmospheric pressure photoionization began being used in atmospheric pressure experiments in the mid 1980s. Early developments in the desorption of open surface and free matrix experiements were first reported in literature in 1999 in an experiment using desorption/ionization on silicon (DIOS). DAPPI replaced techniques such as desorption electrospray ionization (DESI) and direct analysis in real time (DART). This generation of techniques are all recent developments seen in the 21st century. DESI was discovered in 2004 at Purdue University, while DART was discovered in 2005 by Laramee and Cody. DAPPI was developed soon after in 2007 at the University of Helsinki, Finland. The development