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Atmospheric Electricity in Israel

Research

Oct 5th, 2016
Atmospheric Electricity in Israel

New research of PhD Student: Roy Yaniv, Advisors: Prof. Colin Price and Prof. Yoav Yair

Introduction

The global electric circuit (GEC) on earth is driven by electrified shower clouds and thunderstorms. The current flows up to the ionosphere from severe weather regions and returns back to earth in areas known as fair weather regions. The vertical conduction current density (Jz) is of typical value of ~1-2 pA m-2. The vertical electrical field (Ez) is of typical value between 100-300 V/m near ground and correlates with the diurnal thunderstorm activity - known to be the Carnegie curve.

 

Instrumentation

We built 2 measurement stations in Mizpe Ramon and Mount Hermon to measure the parameters of the GEC. 2 conducting plates to measure the conduction and displacement currents. The second station is a rotating Electric field meter (Campbell Scientific).

 

Results

The diurnal changes of the vertical E-field (Ez) in fair weather days in Mitzpe Ramon were found to correlate with the Carnegie curve and are influenced by the morning heating of the sun that lift aerosols and increase the Ez. The results in the Hermon found a greater morning increase as a results from the uplift of a charged aerosol layer to the mountain top in the morning hours in what known as "Austausch". The layer is charged overnight in the surrounded valleys when the inversion is low in what known as the "electrode effect".

 

The fair weather data is used for future studies on the impact of solar storm on the global circuit. We want to study the impacts of daily local changes on the global circuit parameters.

 

Graph of Mean diurnal fair weather behavior of the vertical electric field in Israel

Mean diurnal fair weather behavior of the vertical electric field in Israel

The Electrical Nature of the Atmosphere

Research

Mar 27th, 2016
The Electrical Nature of the Atmosphere

Researcher: Roy Yaniv

Advisors: Prof. Colin Price and Prof. Yoav Yair

The Earth's atmosphere can be described as a huge global electric circuit (GEC). The batteries of the electric circuit are the ~1500 thunderstorms active around the globe at any time.  Each storm produces about 1 Ampere of current that flows up to the ionosphere and returns back to Earth in areas known as fair weather regions, like the Negev Desert. The vertical conduction current density (Jz) measured at the surface in fair weather regions is of typical value of ~1-2 pA m-2. In addition, the ionosphere and the Earth's surface act like a huge spherical capacitor, with a voltage of 250kV between the ionosphere and the Earth.  Near the surface, the vertical electrical field (Ez) is of typical value between 100-300 V/m and correlates with the global diurnal thunderstorm activity - known to be the Carnegie curve.

 

We have built 2 measurement stations in Mizpe Ramon and Mount Hermon to measure the parameters of the GEC. For the Jz we have two conducting plates that measure the conduction and displacement currents (see figure below, right). The second sensor (below, left) is a rotating Electric field meter (Campbell Scientific) used to monitor the changes atmospheric electric field.

 

The diurnal changes of the vertical E-field (Ez) in fair weather days are found to correlate with the global Carnegie curve, but are also influenced by the morning heating of the sun that lifts aerosols into the air and increases the Ez values. We are studying the local and global impacts on the GEC variability, as well as how solar storms impact the GEC.

 

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