Page 1 of 18

European Journal of Applied Sciences – Vol. 11, No. 2

Publication Date: April 25, 2023

DOI:10.14738/aivp.112.14429.

Hoisington, R. D., Whiteside, M., & Herndon, J. M. (2023). Unequivocal Detection of Solar Ultraviolet Radiation 250-300 nm (UV- C) at Earth’s Surface. European Journal of Applied Sciences, Vol - 11(2). 455-472.

Services for Science and Education – United Kingdom

Unequivocal Detection of Solar Ultraviolet Radiation 250-300 nm

(UV-C) at Earth’s Surface

Raymond D. Hoisington

iRay Spectra Metrics, Bakersfield, California 93306 USA

Mark Whiteside

Florida Department of Health, Key West, Florida 33040 USA

J. Marvin Herndon

Transdyne Corporation, San Diego, California 92131 USA

ABSTRACT

The toxicity of ultraviolet radiation in wavelength range 100-280 nm (UV-C) is well

documented. UV-C irradiation can cause skin cancer, premature aging, visual

problems and blindness. Prolonged exposure to UV radiation can kill both plants

and animals, including entire forests. There are numerous assertions in the

medical, public health, and geoscience literature that no UV-C reaches Earth’s

surface, despite several studies to the contrary including one in 2007 by NASA.

Naysayers blame technical problems such as stray light. Low-level UV-C

measurements are difficult, if not nearly impossible, when using low integration

values in the CCD Imaging Spectral Radiometers. This is due to the instrument’s

internal and external atmospheric stray light issues, issues which even occur during

calibration procedures that employ heated filament or gas-filled lamps. To obviate

these inherent problems, one of us (RDH) designed, engineered, and constructed a

Double Monochromator utilized in conjunction with the ILT950UV Spectral

Radiometer operating in the raw data mode. Each of the initial measurements of

solar irradiance displayed evidence of UV-C arriving at Earth’s surface, not high in

the mountains, but just 176 meters above sea-level. These data were taken in the

raw data mode, corrected for prism loss, with instrument noise, i.e. machine errors,

subtracted. The non-zero value for relative spectral irradiance clearly shows the

existence of UV-C at Earth’s surface, in the range 250-300 nm, even when measured

under less than optimum atmospheric conditions. Research and development

continue. We must know with certainty the condition of the stratospheric ozone

layer that shields surface life from solar UV-C. Covert geoengineering atmospheric

particulate pollution, in combination with industrial pollution of the atmosphere,

is killing Earth’s stratospheric ozone layer. If unabated, it will sound the death knell

for much of life on Earth.

INTRODUCTION

Due to stratospheric ozone depletion, increasingly measurable amounts of harmful solar

radiation are reaching Earth’s surface. Extreme ultraviolet radiation (UV) in the form of UV-B

and UV-C leads to serious and irreparable harm. It causes mutations in cellular DNA, which lead

to major alterations in cell function and carcinogenesis. Other damaging effects of this type of

radiation include premature aging, visual problems and blindness, and effects on fertility.

Page 2 of 18

Services for Science and Education – United Kingdom 456

European Journal of Applied Sciences (EJAS) Vol. 11, Issue 2, April-2023

Prolonged exposure to UV radiation can kill both plants and animals, and otherwise make them

more susceptible to disease. Besides their direct biological effects, UV radiation has complex

effects on biogeochemical processes [1].

The toxicity of ultraviolet radiation in wavelength range 100-280 nm (UV-C) is well

documented. UV-C irradiation has lethal effects on insects and microorganisms [2, 3]. UV-C

radiation induces programmed cell death, or apoptosis, in plant cells [4]. In a controlled study,

numerous ultrastructural changes and associated cell damage were shown in mole rat kidney

tissue cells irradiated with artificially produced UV-C radiation [5]. Medical students

accidentally exposed for 90 minutes to UV-C radiation from a germicidal lamp all suffered

reversible photokeratitis, and skin damage to the face, scalp, and neck [6].

For such a dangerous potentiality from solar radiation, it is remarkable that there are numerous

assertions in the medical, public health, and geoscience literature that no UV-C reaches Earth’s

surface [7-13]. Those assertions are even more remarkable considering published evidence

that solar UV-C does in fact reach Earth’s surface [14-17].

In 2007, D’Antoni et al. [16] published spectral irradiance measurements made on two

mountain slopes in Tierra del Fuego, Argentina with elevations ranging 245-655 m. All of their

published results detected significant radiation in the UV-C region. There was criticism of the

article [18] that was later adequately addressed by D’Antoni et al. [19]. Interest in this

important topic disappeared over the next decade. As this was a NASA investigation, it should

have been imperative that NASA take the lead in obtaining the most accurate and precise data

related to solar UV-C reaching Earth’s surface, but that never happened.

We have borne witness to how the natural world is suffering. The richness and diversity of life

on Earth is disappearing at an incredible rate, and there are massive population declines of both

animal and plant life [20-22]. Entire forests are slowly dying and one of the main culprits may

well be increasing UV-B and UV-C [23, 24].

In 2018, we published solar spectrometric measurements that as well demonstrated that UV-C

is reaching Earth’s surface [17], reproduced here as Figure 1.

Page 3 of 18

457

Hoisington, R. D., Whiteside, M., & Herndon, J. M. (2023). Unequivocal Detection of Solar Ultraviolet Radiation 250-300 nm (UV-C) at Earth’s Surface.

European Journal of Applied Sciences, Vol - 11(2). 455-472.

URL: http://dx.doi.org/10.14738/aivp.112.14429.

Figure 1. Comparison of our solar spectrometric measurements [17] with those of D’Antoni et

al. [16].

There is remarkable similarity of our data [17] and those of D’Antoni et al. [16], despite the fact

the measurements were taken using spectrometers by different manufacturers. There are

commonalities, however. Both spectrometers utilized a charge-coupled device (CCD) sensor,

and neither manufacturer would provide complete numerical calibration data.

When science is agenda-driven, as it is now and has been for the last several decades, scientific

objectivity suffers. All too often contradictory measurements, like those of D’Antoni et al. [16],

are simply ignored. Sometimes disinformation agents try to instill doubt by making pejorative

assertions evoking potential spectrometer issues such as those arising from stray light.

Interestingly, in 1997 Córdoba et al. [14, 15] detected solar UV-C radiation at Earth’s surface

using a fundamentally different methodology, employing a KCl: Eu2+ dosimeter, which is not

subject to stray light problems.

We have embarked on a quest to detect solar UV-C irradiance at Earth’s surface in a manner

and with a methodology that eliminates any potential technical error inherent in commercial

spectrometers.

Here we report results of the first step of the investigation, providing unequivocal evidence of

UV-C solar irradiance at Earth’s surface in the range 250-300 nm expressed in relative units.