Sentences with phrase «power dissipation index»

The black curve in both panels shows the departure of the observed Atlantic tropical cyclone power dissipation index from mean conditions for the period 1946 - 2007.

Here, the author draws causality relationships between global mean near - surface air temperatures and Atlantic sea surface temperatures and hurricane power dissipation indexes using statistical causality tests.

There is, however, limited evidence from a relatively short time period that storm strength is increasing, such as the Emanuel (2005) «power dissipation index» of hurricane intensity.

A recent study in Nature by Emanuel (2005) examined, for the first time, a statistical measure of the power dissipation associated with past hurricane activity (i.e., the «Power Dissipation Index» or «PDI» — Fig. 2).

Measure of total power dissipated annually by tropical cyclones in the North Atlantic (the power dissipation index «PDI») compared to September tropical North Atlantic SST (from Emanuel, 2005)

Lin's group determined the cubes of the storms» maximum wind speeds, taken at 6 - hour intervals and integrated over the storms» lifetimes, to obtain each storm's power dissipation index, a measure of the storm's destructive potential.

The upper and lower panels show two different statistical relationships between the power dissipation index and sea surface temperature, one based on actual sea surface temperature (red curve, upper panel) and another based on Atlantic sea surface temperature relative to tropical mean sea surface temperature (cyan curve, lower panel).

Over the past 50 years there has been a strong statistical connection between tropical Atlantic sea surface temperatures and Atlantic hurricane activity as measured by the Power Dissipation Index (which combines storm intensity, duration, and frequency).

• Atlantic tropical cyclone (hurricane) activity, as measured by both frequency and the Power Dissipation Index (which combines storm intensity, duration, and frequency) has increased.

The power dissipation of a storm is proportional to the wind speed cubed (Emanuel, 2005a), as the main dissipation is from surface friction and wind stress effects, and is measured by a Power Dissipation Index (PDI).

Stefan Rahmstorf explains the PDI as, «Concerning the power dissipation index: this is the wind speed cubed, integrated over the surface area covered by the hurricane and over time.»

Observed records of Atlantic hurricane activity show some correlation, on multi-year time - scales, between local tropical Atlantic sea surface temperatures (SSTs) and the Power Dissipation Index (PDI)-- see for example Fig. 3 on this EPA Climate Indicators site.