GB2627929A

GB2627929A - Lightning detection

Info

Publication number: GB2627929A
Application number: GB2303285.7A
Authority: GB
Inventors: John Protts Michael; Mark Horseman Andrew; Prust Stephen; Enno Sven-Erik; Sugier Jacqueline; Keith Stone Edmund; Marlton Graeme
Original assignee: Secretary Of State For Science Innovation And Tech
Current assignee: Secretary Of State For Science Innovation And Tech
Priority date: 2023-03-07
Filing date: 2023-03-07
Publication date: 2024-09-11
Also published as: GB202303285D0; WO2024184422A1

Abstract

A lightning detector 103 comprises: a dipole antenna; detection circuitry to detect a signal exceeding a threshold between the conductors of the dipole caused by an electromagnetic emission generated by lightning; timing circuitry comprising a radio receiver to receive timing data from a remote sender and to generate a timestamp recording the time of detection of the signal by the detection circuitry; and output circuitry to associate the timestamp with the detected signal and output the detected signal and associated timestamp over a network. The location of the lightning may be determined by receiving data from several detectors at a central location determining device 102. The received signals are correlated to detect the same lightning emission at two or more detectors. The corresponding timestamps can then be used in a time difference of arrival method to calculate the position of the lightning. The timestamp may be from a satellite positioning system e.g. GPS.

Description

LIGHTNING DETECTION

Field of the Disclosure

The present disclosure relates to lightning detection.

Background of the Disclosure

Hazardous weather is often associated with thunderstorms, and can include intense precipitation, severe icing, wind shear, turbulence and strong wind gusts. Such weather may have a high human impact, for example, it may impact public safety, aviation, telecommunication and power lines. It is desirable therefore to be able to detect and locate thunderstorms, both to identify current hazardous weather events, and for future weather prediction. Detection of the origin of the electromagnetic emission generated by lightning produced by a thunderstorm is an approach to detecting and locating thunderstorms.

Summary of the Disclosure

An approach to detection of lightning is by detecting components of the electromagnetic field (generally referred to as sferics, an abbreviation of 'atmospherics') that results from the neutralisation of charge caused by the lightning discharge. In particular, detection of low frequency components of the sferic waveforms, for example, in the range of 3-30 KHz can be informative as atmospheric attenuation at these frequencies is relatively low, and the sferic wave can propagate long distances along the earth-atmosphere wave guide, thereby facilitating long-range lightning detection.

Detection of the sferic wave from a lightning discharge at multiple different geographical positions allows determination of the location of the lightning, for example, using the Arrival Time Difference (ATD) location technique. Using the ATD technique, the origin of the lightning stroke can be located using the time differences between the arrivals of the sferic waves at the different detector sites. The precision of the location determination generally increases with the number of different detections.

An approach to detection of the sferic wave is using a detector utilising an electrically short dipole antenna. This however requires for operation a low impedance, quiet ground reference connection. This ground connection typically has two functions; firstly to act as a reference for amplifier components of the antenna, and secondly to act as a surge and over-voltage protection path. This ground connection however may undesirably render the antenna susceptible to ground loop noise, whereby noise on the ground is amplified and added to the signal of interest, thereby impairing accurate and reliable detection of lightning. In particular, the susceptibility to ground noise may undesirably limit the acceptable gain level, thereby reducing the range of detection of the sensor, and so disadvantageously requiring a relatively high number of detectors for lightning detection over a given area.

An objective of the present disclosure is to provide a system and method for detecting and locating lightning over a relatively long range. Long range detection of lightning has the advantage that relatively few detectors are required for lightning detection over a given area, thereby reducing installation and operational cost and complexity. A further objective of the present disclosure is to obviate the need to provide antenna of detectors with potentially costly low-impedance groundings.

A first aspect of the present disclosure thus provides a detector for detecting lightning, comprising a dipole antenna, detection circuitry coupled to the dipole antenna and configured to determine a power value from a frequency spectrum caused by an electromagnetic emission generated by lightning, timing circuitry comprising a radio receiver configured to receive timing data from a remote sender and in response to detection of a signal by the detection circuitry generate a timestamp recording the timing data received at a time of detection of the signal by the detection circuitry; and output circuitry configured to associate the generated timestamp with the detected signal and output the timestamp and the detected signal or a representation thereof over a network.

The provision of the dipole antenna advantageously avoids the requirement for a ground reference for the antenna. This desirably reduces susceptibility to ground loop noise, which facilitates the use of higher gain, which thereby allows longer-range detection of sferic wave.

An advantage of this relatively long-range wave detection is that fewer detectors are required for lightning detection over a given area, thereby reducing installation and operational cost and complexity. A further advantage of removing the requirement for a low-impedance ground reference for the antenna is a reduction in the cost and complexity associated with providing such a low-impedance ground connection.

In an implementation, the detection circuitry comprises amplifier circuitry comprising first and second charge amplifiers configured to generate a differential signal.

In an implementation, the timing circuitry is configured to receive timing data in the form of a periodic pulse sent by positioning satellites.

In an implementation, the detection circuitry is configured to digitise the signal, and the output circuitry is configured to output data representing a digitised representation of the signal associated with the generated timestamp.

In an implementation, the detection circuitry comprises a microcontroller configured to digitise the signal.

In an implementation, the detection circuitry comprises a high-pass filter configured to filter components of the detected signal with a frequency of 50 Hz or higher.

In an implementation, the detector comprises a mast for supporting the dipole antenna in an elevated position above a ground surface.

In an implementation, the detection circuitry, timing circuitry and output circuitry are mounted on the mast.

A second aspect of the present disclosure provides a lightning location determination system for locating lightning comprising: input circuitry configured to receive data representing detected signals and associated timestamps from a plurality of detectors according to any one of the preceding statements over one or more networks, and correlation circuitry configured to correlate waveforms of the detected signals to identify signals corresponding to a same instance of electromagnetic emission generated by lightning, time difference determination circuitry configured, in response to identification of signals corresponding to a same instance of electromagnetic emission generated by lightning, retrieve the received timestamps associated with the signals corresponding to the same instance of electromagnetic emission generated by lightning, and based on the retrieved timestamps and identified signals, quantify differences between the times defined by the timestamps accounting for propagation effects of dispersion and phase shift of the lightning sferic between detectors, and location determination circuitry configured to determine respective locations of the plurality of detectors, and infer an origin of the instance of electromagnetic emission generated by lightning based on the differences between the times defined by the timestamps and the respective locations of the plurality of detectors.

In this second aspect of the disclosure, the lightning location determination system receives detection data from a plurality of the detectors located in mutually different locations. The lightning location determination system determines whether or not the detection instances correspond to a same sferic wave by correlating the digitised waveforms. This technique relies on the condition that a sferic wave has a characteristic shape when digitised (due to the different ways electric charge breaks down in each particular lightning discharge event), and thus this unique waveform shape is used to identify the emission for a lightning discharge arriving at the different detectors. The differences in the sferic wave arrival times at the different sensors, along with data defining the respective locations of the different sensors, may thus be used to determine the location of the lightning discharge.

In an implementation, the lightning location determination system comprises machine-readable memory accessible by the location determination circuitry defining respective locations of the plurality of detectors.

A third aspect of the present disclosure provides a computer implemented method for detecting lightning comprising: detecting, using detection circuitry coupled to a dipole antenna, a signal exceeding a threshold signal level between conductors of the dipole antenna caused by an electromagnetic emission generated by lightning, receiving, by a radio receiver, timing data from a remote sender and in response to detection of a signal by the detection circuitry generating a timestamp recording the timing data received at a time of detection of the signal by the detection circuitry; and associating the generated timestamp with the detected signal and outputting data representing the detected signal and the associated timestamp over a network.

A fourth aspect of the present disclosure provides a computer-implemented method for determining a location of lightning, comprising: receiving data representing detected signals and associated timestamps from a plurality of detectors according to any one of claims 1 to 8 over one or more networks, and correlating waveforms of the detected signals to identify signals corresponding to a same instance of electromagnetic emission generated by lightning, retrieving, in response to identification of signals corresponding to a same instance of electromagnetic emission generated by lightning the received timestamps associated with the signals corresponding to the same instance of electromagnetic emission generated by lightning, and based on the retrieved timestamps and identified signals, quantify differences between the times defined by the timestamps accounting for propagation effects of dispersion and phase shift of the lightning sferic between detectors, and determining respective locations of the plurality of detectors, and infer an origin of the instance of electromagnetic emission generated by lightning based on the differences between the times defined by the timestamps and the respective locations of the plurality of detectors. In an implementation of the fourth aspect, extraction of a sferic waveform can be effected using a continuous wavelet transform that ensures the detected signal has the waveform characteristics of a sferic and allows the reconstruction of the sferic free from noise.

A fifth aspect of the present disclosure provides a computer program comprising instructions, which, when executed by a computer, cause the computer to carry out the method of the third aspect of the present disclosure and/or the fourth aspect of the present disclosure.

A sixth aspect of the present disclosure provides a computer-readable data carrier having the computer program of the fifth aspect of the present disclosure stored thereon.

A seventh aspect of the present disclosure provides a computing system configured to perform the method of the third aspect of the present disclosure and/or the fourth aspect of

the present disclosure.

The foregoing and other objectives are achieved by the features of the independent claims. Further implementation forms are apparent from the dependent claims, the description and the Figures.

These and other aspects of the invention will be apparent from the embodiment(s) described below.

Brief Description of the Drawings

In order that the present invention may be more readily understood, embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 shows schematically an example of a system for detecting and locating lightning, comprising a plurality of lightning detectors and a lightning location determining system; Figure 2 shows schematically components of each of the lightning detectors identified previously with reference to Figure 1; Figure 3 shows schematically functional modules of each of the lightning detectors identified previously with reference to Figure 1; Figure 4 shows schematically components of the lightning location determining system identified previously with reference to Figure 1; Figure 5 shows schematically functional modules of the lightning location determining system identified previously with reference to Figure 3; Figure 6 shows example processes of a method performed by the lightning detectors for detecting lightning; and Figure 7 shows example processes of a method performed by the lightning location determining system for determining a location of lightning detected by the lightning 20 detectors.

Detailed Description of the Disclosure

Referring firstly to Figure 1, an example implementation of the present disclosure is a lightning detection and location determining system 101 for detecting lightning and determining a location of the lightning.

The system 101 comprises a lightning location determining system 102 and a plurality of lightning detectors 103 to 106 located remotely of the lightning location determining system 102 in mutually different locations. Each of the lightning detectors 103 to 106 comprises electrical components for detecting electromagnetic emissions from lightning mounted to a mast which supports the components above a ground surface. Each of the lightning detectors 103 to 106 is in communication with the lightning location determining system 102 via a respective network.

Each of the lightning detectors 103 to 106 is operable to detect electromagnetic emissions, referred to as sferic waves, generated by lightning discharge, and send data representing detection instances to the lightning location determination system 102. The lightning detectors 103 to 106 are substantially alike, as are their modes of operations. Thus, for brevity only the structure and operation of lightning detector 103 is described in detail herein, on the understanding that substantially the same teachings are applicable to lightning detectors 104 to 106 also.

The lightning location determination system 102 is configured to receive data from each of the lightning detectors 103 to 106, and based on the received data, determine an origin of the detected electromagnetic emissions, i.e., a location of the detected lightning discharge.

Detection of lightning and determination of a location of the lightning may desirably facilitate identify of current thunderstorms and prediction of a future path of a thunderstorm.

Each of the networks communicating the lightning detectors 103 to 106 with the lightning location determining system 102 could, in examples, be a network implemented, for example, by a wide area network (WAN) such as the Internet, a local area network (LAN), a metropolitan area network (MAN), and/or a personal area network (PAN), etc. Such a network could be implemented using wired technology such as Ethernet, Data Over Cable Service Interface Specification (DOCSIS), synchronous optical networking (SONET), and/or synchronous digital hierarchy (SOH), etc.) and/or wireless technology e.g., Institute of Electrical and Electronics (IEEE) 802.11 (Wi-Fi), IEEE 802.15 (WiMAX), Bluetooth, ZigBee, near-field communication (NFC), and/or Long-Term Evolution (LTE), etc.). The network may include at least one device for communicating data in the network. For example, the networks may each include computing devices, routers, switches, gateways, access points, and/or modems.

Referring next to Figure 2, in examples lightning detector 103 comprises processor 201, machine-readable storage 202, dipole antenna 203, input/output interface 204, and system bus 205. The lightning detector 103 is configured to run a computer program for detecting electromagnetic emissions from lightning and sending data defining characteristics of such detections to the lightning location determining system 102.

Processor 201 is configured for execution of instructions of a computer program for detecting electromagnetic emissions from lightning and sending data defining characteristics of such detections to the lightning location determining system 102. Storage 202 is configured for non-volatile storage of machine-readable instructions defining the computer program run by the processor 201, and for storing data generated by the computer program. Antenna 203 is a dipole antenna operable to detect electromagnetic emissions from lightning discharge and generate a corresponding electrical signal. Input/output interface 204 is configured to connect the lightning detector 103 to the respective network. The components 201 to 204 of the lightning detector 103 are in communication via system bus 205.

Referring next to Figure 3, in examples the components of the lightning detector 103 support a plurality of functional modules 301 to 303 for detecting a sferic wave generated by lightning discharge and sending data defining characteristics of such detections to the lightning location determining system 102 via the network.

Detection circuitry 301 is coupled to the dipole antenna 203 and is configured to detect an electrical signal generated by the dipole antenna 203 in response to interception of electromagnetic emissions from a lightning discharge. Detection circuitry is configured to compare a detected signal to a predetermined threshold signal level defined in storage 202, and determine if the detected signal level exceeds the threshold level, thereby indicating it to be a signal of interest rather than a background noise signal. Detection circuitry 301 may comprise charge amplifiers configured to generate a differential signal. In the event that the detected signal level exceeds the threshold level, the detection circuitry 301 is configured to digitise the detected signal, and output the digitised signal to the timing circuitry 302.

Timing circuitry 302 is configured to accurately timestamp instances of signals output by the detection circuitry with a timestamp indicating the time of detection of the signal by the detection circuitry, i.e. approximately the time of arrival of the sferic wave at the detector 103. Timing circuitry 302 may comprise a radio receiver to receive accurate timing data from an external source. In an example, a timestamp can be provided for the bufferwithin a stream of data. In examples, timing circuitry 302 comprises a Global Navigation Satellite System (GNSS) receiver, configured to receive a pulse-per-second (PPS) timing pulse from positioning satellites. Such timing data is advantageously highly accurate. Timing circuitry 302 is thereby functional to generate a timestamp for signal detections indicating the time of detection of the signal, and output the timestamp attached to the digitised signal data to the output circuitry. In some examples, timing circuitry can be provided in the lightning location determination system 102. As such, this centrally located timing circuitry can generate a timestamp for signal detections indicating the time of detection of the signal, and output the timestamp attached to the digitised signal data to the output circuitry, such as for signals received from detectors for example, which can include raw (i.e., unformatted and/or unprocessed) data representing a signal detection. For example, a check for spectral energy can be performed at a detector. This check can determine whether a sferic is likely. Detection proper can be performed centrally using the lightning location determination system 102 using raw data received from a detector.

Output circuitry 303 is configured to receive the timestamp and the digitised signal data from the timing circuitry 302, and output the digitised signal data associated with the generated timestamp over the network to the lightning location determining system 102.

Referring next to Figure 4, in examples lightning location determining system 102 comprises processor 401, machine-readable storage 402, input/output interface 403, and system bus 404. The lightning location determining system 102 is configured to run a computer program for determining a location of a lightning discharge based on detection data received from each of the lightning detectors 103 to 106 via the networks.

Processor 401 is configured for execution of instructions of a computer program for determining a location of a lightning discharge based on detection data received from each of the lightning detectors 103 to 106. Storage 402 is configured for non-volatile storage of machine-readable instructions defining the computer program run by the processor 401, and for storing data generated by the computer program. Input/output interface 402 is configured to connect the lightning location determining system 102 to the networks. The components 401 to 403 of the lightning location determining system 102 are in communication via system bus 404.

Referring next to Figure 5, in examples the components of the lightning location determining system 102 support a plurality of functional modules 501 to 504 for determining a location of a lightning discharge.

Input circuitry 501 is configured to receive the digitised signal data and timestamp data output by each of the detectors 103 to 106 via the networks. For each detector 103-106 the circuitry computes a Continuous Wavelet transform which is used to extract the sferic waveform from the digitised signal data for each detector.

Correlation circuitry 502 is configured to pick the receiver 103-106 with the earliest extracted sferic waveform of the received digitised signal data and finds extracted sferic waveforms of the received digitised signal data from the other receivers which have timestamps less than or equal to the time it takes for light to travel to said receivers. The sub selected extracted sferic waveforms of the received digitised data from receivers 103-106 are compared to ensure they have comparable amplitude and are correlated to identify signals corresponding to a same instance of electromagnetic emission, and so to identify signals corresponding to a same lightning discharge.

Time difference determining circuitry 503 is configured, in response to an identification by correlation circuitry 502 of a same instance of electromagnetic emission detected by plural of the detectors, to evaluate the timestamps associated with the respective detection instances, and to quantify differences between the timestamps. In other words, time difference determining circuitry is configured to determine differences between times of detection of a same sferic wave by the plural detectors 103 to 106. The time difference is computed by taking the initial difference of the timestamps which is then refined by addition of the lag of the cross-correlation of the extracted waveforms which also accounts for propagation effects of that detector pair that the time difference is calculated for.

Location determination circuitry 504 is configured to infer an origin of the sferic wave detected by the plural detectors 103 to 106, i.e., identify a location of the lightning discharge event which generated the sferic wave. In examples, this is achieved by an Arrival Time Difference (ATD) location technique. The ATD technique aims to infer an origin of a wave based on differences in times of arrival/detection of the sferic wave at different known locations. Location determination circuitry 504 is thus configured to determine respective geographical locations of the plural detectors 103 to 106. For example, coordinates of the respective location of each of the detectors 103 to 106 may be stored in storage 402, and location determination circuitry 504 may thus retrieve the coordinate data from storage 402. Location determination circuitry 504 is further configured to evaluate the time difference data output by the time difference determination circuitry 503, and thereby infer an origin of the sferic wave. The location determination circuitry is also configured to provide errors and associated Quality metrics on each origin of sferic wave.

Lightning location determining system 102 may be further configured to output data defining the inferred origin and time of the sferic wave, i.e., the time and location of the lightning discharge, for example, in the form of a graphical representation via an electronic display.

Lightning location determining system 102 can also be configures to output the associated errors and quality metrics associated with each lightning location.

Referring next to Figure 6, in examples a method for detecting lightning performed by a computer program run by each of the detectors 103 to 106 comprises four stages 601 to 604.

At stage 601, the dipole antenna 203 is controlled to transduce an electrical signal in response to interaction with a sferic wave. Detection circuitry 301 is controlled to compare the detected signal to a predetermined threshold signal level defined in storage 202, and determine if the detected signal level exceeds the threshold level, thereby indicating it to be a signal of interest rather than a background noise signal.

At stage 602, detection circuitry 301 is controlled to digitise the detected signal, and output the digitised signal to the timing circuitry 302.

At stage 603, timing circuitry 302 is controlled to receive timing data, e.g., to receive a PPS signal provided by a GNSS system. Timing circuitry 302 is then controlled to generate a timestamp for signal detections based on the received timing data, the timestamp indicating the time of detection of the signal. The timing circuitry 302 is then controlled to output the timestamp attached to the digitised signal data to the output circuitry.

At stage 604, the output circuitry 303 is controlled to receive the timestamp and the digitised signal data from the timing circuitry 302, and output the digitised signal data associated with the generated timestamp over the network to the lightning location determining system 102.

Referring next to Figure 7, in examples a method for determining a location of a lightning discharge performed by a computer program run by lightning location determining system 102 comprises four stages 701 to 704.

At stage 701, input circuitry 501 is controlled to receive the digitised signal data and timestamp data output by each of the detectors 103 to 106 via the networks.

At stage 701(a) the input circuitry uses the continuous wavelet method to extract and reconstruct the sferic waveforms from the digitised data signals.

At stage 702, correlation circuitry 502 is controlled to correlate waveforms of the received digitised data to identify signals corresponding to a same instance of electromagnetic emission, and so to identify signals corresponding to a same lightning discharge.

At stage 703, time difference determining circuitry 503 is controlled, in response to an identification by correlation circuitry 502 of a same instance of electromagnetic emission detected by plural of the detectors, to evaluate the timestamps associated with the respective detection instances, and to quantify differences between the timestamps.

At stage 704, location determination circuitry 504 is controlled to infer an origin of the sferic wave detected by the plural detectors 103 to 106, i.e., identify a location of the lightning discharge event which generated the sferic wave, e.g., by an ATD location technique. Stage 704 may thus involve location determination circuitry 504 determining respective geographical locations of the plural detectors 103 to 106. Stage 704 may further involve location determination circuitry 504 evaluating the time difference data output by the time difference determination circuitry 503, and inferring an origin of the sferic wave.

The computer program run by lightning location determining system 102 may further cause the lightning location determining system 102 to output data defining the inferred origin of the sferic wave, i.e., the location of the lightning discharge, for example, in the form of a graphical representation via an electronic display.

Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality.

Claims

Claims 1. A detector for detecting lightning comprising: a dipole antenna, detection circuitry coupled to the dipole antenna and configured to detect a signal exceeding a threshold signal level between conductors of the dipole antenna caused by an electromagnetic emission generated by lightning, timing circuitry comprising a radio receiver configured to receive timing data from a remote sender and in response to detection of a signal by the detection circuitry generate a timestamp recording the timing data received at a time of detection of the signal by the detection circuitry; and output circuitry configured to associate the generated timestamp with the detected signal and output data representing the detected signal and the associated timestamp over a network.
2. The detector of claim 1, wherein the detection circuitry comprises amplifier circuitry comprising first and second charge amplifiers configured to generate a differential signal.
3. The detector of claim 1 or claim 2, wherein the timing circuitry is configured to receive timing data in the form of a periodic pulse sent by positioning satellites.
4. The detector of any one of the preceding claims, wherein the detection circuitry is configured to digitise the signal, and the output circuitry is configured to output data representing a digitised representation of the signal associated with the generated 25 timestamp.
5. The detector of claim 4, wherein the detection circuitry comprises a microcontroller and an analogue to digital converter (ADC) configured to digitise the signal.
6. The detector of any one of the preceding claims, wherein the detection circuitry comprises a high-pass filter configured to filter components of the detected signal with a frequency of 50 Hz or higher.
7. The detector of any one of the preceding claims, comprising a mast for supporting the dipole antenna in an elevated position above a ground surface.
8. The detector of claim 7, wherein the detection circuitry, timing circuitry and output circuitry are mounted on the mast.
9. A lightning location determination system for locating lightning comprising: input circuitry configured to receive data representing detected signals and associated timestamps from a plurality of detectors according to any one of claims 1 to 8 over one or more networks, and correlation circuitry configured to correlate waveforms of the detected signals to identify signals corresponding to a same instance of electromagnetic emission generated by lightning, time difference determination circuitry configured, in response to identification of signals corresponding to a same instance of electromagnetic emission generated by lightning, retrieve the received timestamps associated with the signals corresponding to the same instance of electromagnetic emission generated by lightning, and based on the retrieved timestamps, quantify differences between the times defined by the timestamps, and location determination circuitry configured to determine respective locations of the plurality of detectors, and infer an origin of the instance of electromagnetic emission generated by lightning based on the differences between the times defined by the timestamps and the respective locations of the plurality of detectors.
10. The lightning location determination system of claim 9, comprising machine-readable memory accessible by the location determination circuitry defining respective locations of the plurality of detectors.
11. A computer implemented method for detecting lightning comprising: detecting, using detection circuitry coupled to a dipole antenna, a signal exceeding a threshold signal level between conductors of the dipole antenna caused by an electromagnetic emission generated by lightning, receiving, by a radio receiver, timing data from a remote sender and in response to detection of a signal by the detection circuitry generating a timestamp recording the timing data received at a time of detection of the signal by the detection circuitry; and associating the generated timestamp with the detected signal and outputting data representing the detected signal and the associated timestamp over a network.
12. A computer-implemented method for determining a location of lightning, comprising: receiving data representing detected signals and associated timestamps from a plurality of detectors according to any one of claims 1 to 8 over one or more networks, and correlating waveforms of the detected signals to identify signals corresponding to a same instance of electromagnetic emission generated by lightning, retrieving, in response to identification of signals corresponding to a same instance of electromagnetic emission generated by lightning the received timestamps associated with the signals corresponding to the same instance of electromagnetic emission generated by lightning, and based on the retrieved timestamps, quantifying differences between the times defined by the timestamps, and determining respective locations of the plurality of detectors, and infer an origin of the instance of electromagnetic emission generated by lightning based on the differences between the times defined by the timestamps and the respective locations of the plurality of detectors.
13. A computer program comprising instructions, which, when executed by a computer, cause the computer to carry out the method of claim 11 or claim 12.
14. A computer-readable data carrier having the computer program of claim 13 stored thereon.
15. A computing system configured to perform the method of claim 11 or claim 12.