[Source_Name: Short_Name='FIXED OBSERVATION STATIONS']
Daily broad-band ultra-violet radiation observations using biologically effective UVR detectorsEntry ID: ARPANSA_BIO
Abstract: This dataset also forms part of the set of State of the Environment (SOE) indicators.
Daily measurements of solar Ultra-Violet radiation at Casey and Davis stations, reported in units of standard erythemal dose (SED).
TYPE OF INDICATOR
There are three types of indicators used in this report:
1.Describes the CONDITION of important elements of a system;
2.Show the extent of ... the major PRESSURES exerted on a system;
3.Determine RESPONSES to either condition or changes in the condition of a system.
This indicator is one of: CONDITION and PRESSURE
RATIONALE FOR INDICATOR SELECTION
Stratospheric ozone depletion began in the mid-1970's and is likely to persist until mid this century or beyond. Ozone depletion allows more short wavelength, biologically damaging, UVB radiation (280-320 nm) to reach the Earth's surface. Thus, organisms living beneath depleted ozone are likely to be impacted by enhanced UVB irradiances. Enhanced UVB irradiances can increase the incidence of skin cancer, cataract eye disease and even immune system suppression in humans. It can also reduce the growth, productivity and survival of marine organisms and can cause changes in the structure and function of Antarctic marine communities. This indicator provides a direct measure of the extent and magnitude to which UV irradiances are enhanced and provides vital data against which biological responses to UV exposure can be normalised.
Living organisms are sensitive to UV radiation because vital biological molecules such as DNA, lipids and proteins absorb strongly in these wavelengths. DNA, with a peak absorption at 260 nm, is particularly sensitive, and is liable to mutation. DNA damage has been extensively studied in microbial and mammalian systems where UV-induced damage produces two distinct effects, mutagenesis and toxicity. In humans the impact of DNA damage manifests mainly as skin cancer. DNA damage in plants has been the subject of relatively few studies (Britt, 1999; Taylor et al, 1996; Vornarx et al, 1998) with most research examining impacts of UV-B on growth or photosynthesis, predominantly using crop plants. Terrestrial plants are potentially very vulnerable to UV-B induced DNA damage. Firstly the levels of UV-B are higher on land than in water. In addition plants rely on light for photosynthesis and are therefore adapted to absorb high levels of solar radiation (and the associated, harmful UV-B). Defence mechanisms to protect against damaging high energy UV radiation are also found in plants. Compounds such as flavonoids, and carotenoids absorb UV radiation and act as sun-screens, reducing the levels of UV-B at the molecular level. Research has been limited in Antarctic plants but there are clear differences in protective pigment levels in 3 Antarctic mosses with Grimmia antarctici (an endemic species) showing low levels of these pigments compared to other cosmopolitan species (Robinson et al 2001). This suggests that the endemic species may be more vulnerable to UV-B damage. Studies have recently commenced to investigate DNA-damage in these plants. Work by Skotnicki and coworkers (Skotnicki et al 2000) which shows high levels of somatic mutation could also be a result of UV-B exposure.
DESIGN AND STRATEGY FOR INDICATOR MONITORING PROGRAM
Spatial Scale: The Australian Radiation Protection and Nuclear Safety Agency take broadband in situ observations at Antarctic mainland stations (Casey, Davis and Mawson) and at Macquarie Island.
Frequency: Continuous measurements
Measurement Technique: Broad band UV radiometry (use of biometer or biologically effective UVR detector). Total UVR measurements are also made using an Eppley TUV radiometer (responds across 290 to 400 nm wavelength range). Spectral measurements have also been made at Davis station. Readings are taken every ten minutes and the total SED's calculated for the day.
A need exists for a comprehensive monitoring network of broadband measurements, complemented by a small baseline network of precision spectral measurements across the nation. Such a network is being planned by the Bureau of Meteorology to link directly with the basic national meteorological observations. Validation of satellite data with surface based measurements (ARPANSA) over Australia for the period 1979-1992 has been carried out (Udelhofen et al 1999) and a follow up is planned for 1992-2000. Validation of satellite data and surface UVR measurements over the Antarctic and sub-Antarctic is planned between the Antarctic Division, ARPANSA and Dan Lubin at UCLA.
LINKS TO OTHER INDICATORS
SOE Indicator 9 - Daily records of total column ozone at Macquarie Island
10 minute averages of weighted UVR (CIE 1987 spectral effectiveness).
The data in the files is :
Date, time, total solar radiation (counts), gain 1, Total UVR (counts), gain 2, UVB(counts), gain 3, biometer , temperature.
Main Detector is Solar Light UVBiometers (SL501)
Detector 1 - Eppley total solar radiation pyranometer.
Detector 2 - Eppley total UVR (TUV) radiometer - covers wavelength range 290 to 400 nm.
Detector 3 - International Light UVB radiometer - covers wavelength range 290 to 315 nm.
Detector 4 - Solar Light UVBiometer (SL501) - approximates CIE erythemal spectral effectiveness.
The 2nd last column is the biometer in MEDs/hr (1 MED is 200 J/m2 effective weighted with the CIE (1987) erythemal response) and the last column is temperature inside the detector.
The 3 other detectors, with outputs in counts, are the total solar, Total UVR (TUV) and the UVB.
Data are stored as zipped up .dat files.
The fields in this dataset are:
Total Solar Radiation (counts)
Total UVR (counts)
(Click for Interactive Map)
Quality The amount of solar ultraviolet radiation (UVR) reaching the ground is controlled by physical factors including the height of the sun in the sky, time of day, cloud cover, ozone concentrations overhead and reflectance at the surface by ice and snow (albedo). In Antarctica, the combination of these factors leads to erythemal irradiances higher than those experienced in the tropics.
The ... energy of solar radiation, and thus its capacity to damage life in Antarctica, increases with decreasing wavelength. Ozone depletion specifically enhances the shorter wavelengths of the UV spectrum (UVB 280 to 320 nm). Measurements of solar UVR in the past have generally been of either UVR (280 to 400 nm) or more importantly, UVB (280 to 315 nm); these lower wavelengths are very effective in producing damaging biological effects. More recently, in order to relate UV flux measurements to human health, biologically effective UVR is measured using a radiometer that approximates the response of human skin to different wavelengths of UVR. This erythemal spectral effectiveness was defined by the Commission Internationale d E'clairage (International Lighting Commission - CIE) in 1987. The units are minimal erythemal doses (MED) where 1 MED is the amount of UVR required to induce erythema or sunburn in people with sensitive skin.
Ten-minute readings are added together to provide an indication of the total UVR incident at the surface each day. Daily readings of biologically effective solar UVR is in standard erythemal doses (SEDs : 1 SED is 100 J/m2 effective).
For quality-controlled data, the trends in UV can be analysed and compared with those in ozone. The interannual variability due to variations in ozone, cloudiness and other atmospheric parameters needs to be accounted for.
These data (Mawson in particular) could be subject to change upon revision of the calibrations at a future date. Unfortunately there is a large gap in the data from Davis.
There are currently some data gaps for Mawson and Macquarie Island. The Macquarie Island instrument failed in November 2007 and Mawson failed in December 2007. The replacement equipment was installed in late April 2008. Due to ARPANSA IT issues connection to the instruments took some time.
Note that the most recent excel spreadsheet stored in the download file will be the most accurate, and should be used in preference to all other excel spreadsheets, or .dat data.
Access Constraints These data can be viewed at the URL given below for 'Display Antarctic State of Environment Indicator 10', or alternatively, downloaded as a file from the provided URL. The download file contains a number of zipped .dat files and two excel spreadsheets, one for data as it stood in mid-2007, and one for data as it stood in mid-2008.
Use Constraints This data set conforms to the PICCCBY Attribution License
Please follow instructions listed in the citation reference provided at http://data.aad.gov.au/aadc/metadata/citation.cfm?entry_id=ARPANSA_BIO when using these data.
Data Set Progress
Role: TECHNICAL CONTACT
Phone: (785) 628-5367
Fax: (785) 628-4153
Email: bigh at fhsu.edu
Department of Biology Fort Hays State University
City: Fort Hays
Province or State: Kansas
Postal Code: 67601-4099
Role: DIF AUTHOR
Phone: (865) 574-7447
Email: uso at daac.ornl.gov
ORNL DAAC User Services Office Oak Ridge National Laboratory
City: Oak Ridge
Province or State: TN
Postal Code: 37831-6407
Extended Metadata Properties
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Creation and Review Dates
DIF Creation Date: 1998-06-11
Last DIF Revision Date: 2012-10-24