Global warming hiatus Global warming hiatus A global warming hiatus, also sometimes referred to as a global warming pause or a global warming slowdown, is a period of relatively little change in globally averaged surface temperatures. In the current episode of global warming many such 15-year periods appear in the surface temperature record, along with robust evidence of the long-term warming trend. Such a "hiatus" is shorter than the 30-year periods that climate is classically averaged over. Publicity has surrounded claims of a global warming hiatus during the period 1998–2013. The exceptionally warm El Niño year of 1998 was an outlier from the
Temporal logic of actions expression means the value of "x" "today", plus the value of "x" "tomorrow" times the value of y "today", equals the value of "y" "tomorrow". The meaning of formula_1 is that either A is valid now, or the variables appearing in t do not change. This allows for stuttering steps, in which none of the program variables change their values. Temporal logic of actions Temporal logic of actions (TLA) is a logic developed by Leslie Lamport, which combines temporal logic with a logic of actions. It is used to describe behaviours of concurrent systems. Statements in temporal logic are of