Theodore J. Cohen’s research while affiliated with Louisiana State University of Alexandria and other places

What is this page?


This page lists works of an author who doesn't have a ResearchGate profile or hasn't added the works to their profile yet. It is automatically generated from public (personal) data to further our legitimate goal of comprehensive and accurate scientific recordkeeping. If you are this author and want this page removed, please let us know.

Publications (3)


The “Spectra” of the solar cycle and of data for Atlantic tropical cyclones
  • Article

July 1975

·

27 Reads

·

47 Citations

Nature

Theodore J. Cohen

·

Erton I. Sweetser

TROPICAL cyclones (including hurricanes) are significant climatic features which affect the South and East USA as well as areas of the western Atlantic, the Caribbean, and the Gulf of Mexico. Since they are considered to be a mechanism which limits the build-up of heat and energy in tropical regions1, cyclones are necessarily related to large scale circulation patterns which may be global in extent. Thus, if a relationship is to be found between solar activity and large scale meteorological phenomena, we may expect that it will evidence itself in analyses of data on cyclone occurrence and the length of the cyclone season. Here we report results of such a study, and provide evidence which is consistent with the hypothesis that a relationship exists between the solar cycle and the occurrence of Atlantic tropical cyclones.


Evidence Consistent with a Multiple-Event Mechanism for Large Earthquakes

December 1974

·

2 Reads

·

2 Citations

We analyzed the short-period codas of 418 small events (NOS mb ≤ 5.8) and 148 large-events (NOS mb, NOS Ms, or mb from Pasadena or Berkeley ≥7.0). The normalized large-event codas are found to be significantly larger at any given time after the first-arrival onset than corresponding values for small-event codas. This suggests that large events are multiple events, and that the occurrence of later events in a given sequence retards coda decay and elevates the relative amplitudes of the codas above those expected for a small (single) event. Large events are also found to be emergent, displaying a 0.2 to 0.3 mb increase in amplitude between 5 and 30 seconds after the P wave arrival over that observed in the first 5 seconds after the arrival. Coda decay characteristics for large events may be used to estimate the length of the fault zone. We suggest that multiple events are a more common phenomenon than has been generally suspected, and that most if not all events of high or intermediate Ms are probably multiple events.


Long term periodicities in the sunspot cycle

August 1974

·

19 Reads

·

107 Citations

THE existence of a long period undulation (~179 yr) in the solar cycle (Fig. 1, based on data from Waldmeier1,2 is suggested by the planetary theory of sunspots. Jose3, for example, postulated an association between the 178.8-yr periodicity in orbital positions of the planets and the phase of the solar cycle. Wood4 used the presumed existence of a cycle of 170–180 yr in solar activity to predict the peak dates of future sunspot cycles. Our work indicates that although a 179-yr periodicity does exist in the sunspot cycle, it is not caused by a primary long term excitation function but is, instead, a beat phenomenon. This can be seen by computing the spectrum for the data shown in Fig. 1.

Citations (2)


... However, one aspect that remains a gray area is how solar variability affects TC activity. Cohen and Sweetser (1975) directly looked into a possible relationship between TCs and solar activity. The authors did a spectral analysis of smoothed TC count, TC season length (7-year running averages) for the Atlantic basin, and sunspot number (SSN) (12-month running average) data and suggested a possible relationship between Atlantic TC activity and solar cycle. ...

Reference:

Effects of Solar Variability on Tropical Cyclone Activity
The “Spectra” of the solar cycle and of data for Atlantic tropical cyclones
  • Citing Article
  • July 1975

Nature

... The exception is the solar tide driven nature of sunspot activity (Losh, 1927;Usoskin et al., 2007;Cartier, 2019). The periodicity of sunspot activity has been well documented and studied to define an average cycle (Schuster, 1906;Cohen & Lintz, 1974;Kilcik et al., 2014). Sunspot activity is a relevant short-term climate driver, with increased solar radiative output experienced during heightened sunspot activity that impacts sensible weather (Ansor et al., 2023;MacBride, 2023). ...

Long term periodicities in the sunspot cycle
  • Citing Article
  • August 1974