\input a4_12.ltx
\input mypdf.lt
\input myhtml.lt
\pagestyle{plain}
\addtolength{\footskip}{\baselineskip}
\usepackage{times}
\begin{document}
\title{\bfseries
Light as a Pollutant of the Night Environment: reality, impacts,
remedies \\[5mm]
\mdseries \Large Description and Substantiation of the Project \\
submitted to the Czech Science Foundation}
\author{Jan Hollan}
\date{Apr 9, 2004, amended Aug 25}
\maketitle
\begin{htmlonly}
\tableofcontents
\end{htmlonly}
\section{Current knowledge and the results of our grant from 2003}
Pollution of the night environment by artificially added light as an
``airborne'' pollutant is increasingly considered as a serious issue.
Articles and programmes in both the leading world media and local
media all over the world suggest this, as does the existence of and
preparation of relevant local and regional laws.
However, there had been little knowledge about the extent and impact
of this pollution. Our short research project from autumn 2003
(VaV/740/3/03) funded by the Czech Ministry of Environment contributed
a lot to learning this issue. For Czech readers, its final report
summarised the knowledge existing prior to our research (quite often
for the first time in Czech language). From the viewpoint of science,
it opened new fields of research, formulated novel methods of
measurement of light, and collected unique data on the state of night
environment and of impacts of its being polluted by light.
People reading Czech can find the whole set of results at
\h{recetox.muni.cz/noc} -- there is the report with attachments from
many authors, as well as the directories with images and data referred
to in these texts. It's a huge amount of information from many
disciplines, which waits for translation into English to become
accessible to the world public.
\section{Why further research is needed}
In principle, it might not be necessary to study the problem any more, as
far as the restoration of the night environment is concerned (or just
conservation, in those rare regions with an unpolluted night). The ways to
protect the night environment are well known to the handful of principal
world experts, there is a consensus as to which measures are ``necessary and
sufficient'' to reverse the growth of pollution, and cause its steady decline.
Theoretical \wwwt{papers by Pierantonio Cinzano}
{http://dipastro.pd.astro.it/cinzano/papers.html}
show that well enough. Laws
valid in two Italian regions, Lombardy and Marche are an excellent
example: with just minor additions, they will be able to realise this
reversal. Even current development is very positive already.
The minor additions concern lighting of advertisements etc. and are
included in the proposal for a bill to be included into the existing
Czech Clean Air Act (see \h{www.astro.cz/darksky} in English or
\h{www.veronica.cz/noc} in Czech).
However, politicians and clerks in the national, regional and local
executives are no experts on night environment and they don't readily
understand theory of light propagation in the atmosphere, theory of
twilight and nighttime vision, and not even the quantities and units used
in photometry. They can be under an influence of the business
connected with artificial lighting -- various representatives of this
business are often considered as experts (if not the \emph{only} experts) on
lighting, which they of course consider to be entirely beneficial
wherever added to the previously unlit environment. There is a lot of
examples, when the initial political goodwill to do something against
light pollution has been invalidated by the influence of lighting
industry or its R\&D institutes. Either no laws have been introduced
in such cases, or ones which not even slow down the
rise of pollution, but make a wonderful excuse for it as well: our
brave new lighting is made according to the anti-pollution law, so it
does not pollute at all, nobody can object to it! ``Junk science''
financed by lighting industries in the UK led the British Home Office
to the erroneous recommendation that adding more light can reduce
crime (see a short article by
\wwwt{Marchant, 2003}
{http://www.amsta.leeds.ac.uk/statistics/rss/DemoClaimUnf1A.pdf}).
Not only is that nonsense with
no foundation in true research results (it's based just on a common
superstition), but it seems to be really counterproductive (the only
correlation between lighting and crime found up to now is a positive
one, i.e. stronger lighting leads to rise in crime,
\wwwt{Clark 2003}{http://amper.ped.muni.cz/light/crime}). The
only ones who profit are the lighting businesses...
Restoration of the night environment to a healthy, pleasant and safe
state should become a process which starts not just very
exceptionally in isolated places, but everywhere on a national and
then continental level. To make it true, much more knowledge has to
be accumulated. So much that the problems, consequences and remedies
will be evident to the environmentalists of all kinds, to the general
public, politicians and executives. Exactly as with another kinds of
pollution, where the process of cleanup started long ago and
had been successful (many kinds of the chemical pollution of the
atmosphere and of freshwater systems).
\section{Scotobiology}
The science of night environment is just emerging. One of the
milestones had been the Ecology of the Night conference in September
2003 in Muskoka, Ontario, Canada. The new discipline,
\emph{scotobiology},
had been invented (or named) during its preparation (Bidwell 2002), see
\h{ecologyofthenight.org}. Prior to that, two important meetings
marked the way: one on influences of light-at-night on endocrinology
and cancers (see \h{www.uni-koeln.de/symposium2002}), the other on
the wildlife (\h{urbanwildlands.org}). Before that, most of the
concern had been devoted to the artificial skyglow only, at many
meetings attended predominantly by astronomers.
\section{Our goals}
\subsection{Luminance of the sky as an indicator}
Curiously, even the original astronomical concern about the increased
skyglow has seldom been treated in a scientific way. There is
a marked lack of quantitative data on skyglow, i.e., the artificial
increase of the luminance of the night sky. The only comprehensive set
exists for Italy, again thanks to the efforts of Cinzano et al. Sky
luminance in the rest of the world, with the exception of just a couple
of observatories, is computed only on the basis of satellite
measurements of terrestrial emissions (the famous \wwwt{World Atlas of
Artificial Sky Luminance}{http://dipastro.pd.astro.it/cinzano/papers.html}
is again largely a product from the only
scientific institute dealing with light pollution, established and led
by Pierantonio Cinzano,
\wwwt{ISTIL}{http://www.inquinamentoluminoso.it/istil}).
In our short introductory research from autumn 2003, we got some sky
luminance data for one new site at least, namely for the Brno
observatory. Much more data can be processed for this site, from the
huge amount of photometric observations carried out there in past
decades and made further on. The same task can and should be done for
another Czech observatories. The evaluation process should become so
well automated, that most European and world observatories, both
professional and amateur ones, could be included later. Getting
reliable data on sky luminances (for various weathers, landscapes and
times) is achievable and much needed.
One very practical question can be answered this way. Lighting
professionals don't read papers on the science of light
pollution\footnote{I'd be happy to learn if there is an exception, please
inform me...}. They still claim that most of the light pollution
comes inevitably from the lit ground, and that the polluting
influence of direct light from the luminaires is unimportant, as far
as skyglow is concerned. Fortunately, there is a simple way of
demonstrating the role of direct light. If there is a snowstorm and
the sky clears short after it, the ground is white, dispersing six
times more light then a bare winter ground. If the skyglow would rise
six times as well, then the role of direct light would be proven to
be zero. If it rises just three times, it would mean that the
influence of direct light for snow-less conditions is dominant; if it
rises less then twice, then the influence of snow-less lit terrain on
the sky luminance would be proven as really small: excluding direct
upward light, the sky could be up to five times darker without any
reduction of the illumination of the ground. Preliminary results show
that even inside a city (Brno) this latter case may hold. To get
persuasive answers, processing a rich series of old measurements
should help, including those of atmospheric transparency. The
corresponding data on the snow cover can be obtained from the
weather service.
In our previous grant, we have developed methods of measuring the sky
luminance by standard astronomical means, but also of measuring it by
ordinary modern digital cameras. The latter way means better
portability and possibility to investigate various sites easily and
cheaply. By this method we've measured e.g. the luminance of the major
aurora of Nov 20, 2003: they have been from less then one millinit
to maximum of ten millinits. Regarding that the polluted Brno sky has
typically some five millinits, it means that fainter parts of aurora
are hardly visible (they are discernible just if they are deep red,
a colour fortunately typical for extremely strong aurorae) and even the
strongest aurora events mean just a rather inconspicuous change of the
standard city sky...
\subsection{Glare as a main hindrance to seeing the Universe}
During the Ecology of the Night conference, I proposed creation
of glare-free and broad-horizon sites in cities, from where the
twilight landscape and night sky could be admired. Our research from
autumn 2003 proved that people are aware that the main reason why they
don't see stars is not skyglow, but glare from
luminaires. This is something we want to investigate further: how much
it helps when glare is prevented. The target group will be not
just people with normal sight, but also people with sight
disabilities. Some of them may be able to see stars, when observing
from a place where the stars will be the only prominent objects.
Maybe, for the first time in their lives.
\subsection{Glare as an aesthetic and safety problem}
There are many cases where the visibility of the night landscape is
seriously damaged by directly visible light sources and other glaring
areas (space angles, to be accurate). We have collected many images
of such scenes, which deserve to be processed and evaluated; many
more should be taken at night at various sites, to illustrate the
seriousness of the problem. Our method enables to evaluate glare
quantitatively, with digital images. Parallel field experiments with
people with sight disabilities should be made, to study how badly the
common glaring lighting systems serve their purpose, and how large is
the advantage of using the best available technology with as little
glare as possible.
Attitudes of the public to changing the glaring lighting at selected
sites to a quality, low-glare lighting should be studied, together with
documenting the change with digital imaging photometry.
\subsection{Health issues}
Dark is as necessary for us as light. This knowledge is somehow
expressed in the very beginning of
\wwwt{Genesis}{http://mb-soft.com/believe/txs/genesis.htm}.
Whereas the probable
contribution of lack of darkness to rising incidence of cancers
is now being studied, the very simple fact that people sleep worse in
the absence of dark is still beyond the scope of science. Our past
grant brought one of the first results on this issue. One third of
Czech people suffers from insufficient dark for sleep and five per cent
report it as a major reason of sleep problems. The levels of pollution
of darkness by light which are perceived as already unpleasant or
disturbing should be investigated. At the moment we can't say much
more that one millilux of illuminance of the face is very probably
tolerable.
We have an indication, that light at night causes hypertension.
More data on blood pressures should be obtained, together with
measuring the actual light levels.
``Light'' is perhaps not the best word, as this is something we
\emph{see}.
For some purposes, as the synchronisation of the circadian rhythm,
a \emph{non-imaging} visual apparatus (unknown in the past
millennium) is important, whose sensitivity has
a narrow peak in the blue region. Let's call it \emph{melanoptic
vision}. We've
got a hint that this system's sensitivity matches quite well the
sensitivity of blue pixels of digital cameras. The \emph{melanoptic
luminance} of our night environment is the influence which
disturbs the circadian rhythm and leads probably to more cancers. We
should develop our radiometry methods to the stage when we will be
able to report photopic, scotopic and melanoptic ``light'' quantities,
i.e. introduce melanoptic lumens and luxes.
\subsection{Wildlife}
It is suspected that due to lighting, populations of night-active
insects have been diminished by an order of magnitude in urbanised
areas (Eisenbeis 2001 and Povoln\'y 2003). It's not easy to get data on
the abundance of populations half a century ago, but it may be
possible. A \wwwt{recent British survey}
{http://www.butterfly-conservation.org/ne/news/extinction/}
collected such data; we hope that
day and night animals could be distinguished in them, to identify the
damaging role of light at night.
Another unresolved issue which at the is that of light levels
in the national parks and another protected areas at night. From
Cinzano's work, some results can be obtained for clear-sky
conditions. Real measurements were made in US national parks
recently (\wwwt{Moore
2003}{http://www.muskokaheritage.org/ecology-night/chad-moore.asp}).
However, in the case of Czech national parks,
there is often more light when the sky is overcast,
especially when the landscape is covered with snow.
Observers of night nature, as well as hunters, are well aware of the very
different behaviour of animals in moonlit and moonless nights. What is
the influence of constant lighting, mimicking full-moon nights for all
winter?
Unusual behaviour of birds in urbanised areas is often mentioned by
ordinary people: some birds are confused to such an extent that they
begin to sing deep in the night, with an erroneous assumption that
twilight has begun. What does this misleading light signal do to
bird reproduction and numbers?
Sterility of urbanised areas lit by glaring luminaires, as regards
insects and the food-chain dependent on them, has been not investigated
yet. We have proven that shielding a luminaire helps a lot, in our
previous research (Pavel B\'\i{}na did the study).
\subsection{Remedies}
We should make an experiment, where we will shield all luminaires
within a village, and study the revitalisation of the area as far as
wildlife is concerned. Also, we should ask the public how they like
diminished pollution of their bedrooms and reduced glare.
\section{Our background}
Our team is perhaps the only one in the world which is able to do such
a multidisciplinary research. The only other night-research team
we are aware of is that of the
\wwwt{Institute of Science and Technology of Light Pollution}
{http://www.inquinamentoluminoso.it/istil}
from Italy.
Our scope seems to be a bit broader, concerned
with health and wildlife as well, not so much with astronomy-related
issues. The grant for which we apply should enable us to proceed in
the research we began in autumn 2003 (as mentioned above,
its results are available at \h{recetox.muni.cz/noc}).
It is a pioneering work in the
world context, something the Czech Republic can be proud about.
\section{Addendum on Obesity and Lack of Darkness}
Just recently, Apr 5, I remembered one important issue which should be
investigated. I mean the influence of artificial lighting on obesity.
Obesity of more and more people including children is a quickly
expanding disaster. I think I have read somewhere (I don't remember
where, perhaps it had been of US origin\footnote{I found it on Aug
22-24, thanks to a very interesting new paper -- Stephen M. Pauley:
\wwwt{Lighting for the human circadian clock: recent
research indicates that lighting has become a public health issue.}
{http://www.sciencedirect.com/science/issue/6950-2004-999369995-514479}
\emph{Medical Hypotheses} Vol. 63, 4, 2004, pp 588-596
-- as the last reference there. Searching info on that reference,
I revealed I read about the problem years ago already in the 2000 version of
Dr. Clark's revealing paper (see
\h{amper.ped.muni.cz/light/crime}), the very paper I
studied thoroughly and proudly put on my website!
Clark summarizes the book by Wiley and Formby, see
the end of this obsolete Addendum by an oblivious author...
})
that a seasonal signal of
nights getting longer in late summer and autumn is masked by
artificial lighting. As many boreal animals accumulate fat in that
period, to survive winter and eventually to have offsprings, we can
speculate people do the same. This used to be a vital adaptation
until not much more than a century ago. However, winter never
comes in our time, so accumulation of fat (or appetite to eat more than
needed) proceeds unchecked.
When I mentioned this missing long-night signal (during some break at the
Ecology of the Night conference), \wwwt{Steven
Lockley}{http://www.muskokaheritage.org/ecology-night/steven-lockley.asp}
suggested a possible different mechanism, namely a year-round sleep
deprivation. We can guess there had been enough time for sleep in winter
until expansion of electric lighting, and enough dark to sleep well.
As we are aware of possible causal links between lack of dark and
obesity, and of the problem obesity presents for the rich part of
our world, we have to include the problem in our research.
This is something which should be mentioned e.g. at
\wwwt{the First Joint Meeting of SLTBR
and AAMCC}{http://www.sltbr.org/2004program.htm}.
Sparse
relevant links on seasonal changes in fat accumulation
I found on Internet initially are by Petteri
Nieminen,
\wwwt{\textit{The (un)natural history of endocrine weight-regulation}}
{http://cc.oulu.fi/~ehohtola/nieminen.pdf} and a purely zoological
abstract on lemmings by Hunter HL, Nagy TR,
\wwwt{\textit{Body composition in a seasonal model of obesity...}}
{http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12429883&dopt=Abstract}.
The length of interval of night melatonin secretion had surely been
seasonally dependent in humans in a natural boreal environment, as
contrasted to early research results for young Czech scientists (working
hard all the year round...) -- as I learned from a recent lecture of
\wwwt{Helena Illnerov\'a}{http://www.cas.cz/en/Council/Text/Illnerova.htm} here in
Brno.
%there is surely a series of papers on that, I just don't know
%he exact references at the moment).
Some relevant papers found in
\www{PubMed}{http://www.ncbi.nlm.nih.gov/entrez}
(I know just the abstracts):
\begin{htmlonly}
\begin{itemize}
\end{htmlonly}
%begin{latexonly}
\bie
%end{latexonly}
\raggedright
\item
No seasonal difference in the duration of elevated night melatonin
concentration was found in an early work \\
Illnerova H, Zvolsky P, Vanecek J:
\wwwt{ The circadian rhythm in plasma melatonin concentration
of the urbanized man: the effect of summer and winter time.}
{http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=3971177}
\emph{Brain Res.} 1985; 328:186-189.
\item
Such a difference has been found in \\
Vondrasova D, Hajek I, Illnerova H:
\wwwt{Exposure to long summer days affects the human melatonin
and cortisol rhythms.}
{http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=9219878}
\emph{Brain Res.} 1997; 759:166-170.
\item
An earlier research showing seasonal varition is \\
Stokkan KA, Reiter RJ:
\wwwt{Melatonin rhythms in Arctic urban residents.}
{http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=8158521}
\emph{J Pineal Res.} 1994 Jan;16(1):33-6.
\item
Increased obesity risk is mentioned in \\
Qin LQ, Li J, Wang Y, Wang J, Xu JY, Kaneko T:
\wwwt{The effects of nocturnal life on endocrine circadian patterns
in healthy adults.}
{http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12954455}
\emph{Life Sci.} 2003 Sep 26;73(19):2467-75.
\begin{htmlonly}
\end{itemize}
\end{htmlonly}
%begin{latexonly}
\ei
%end{latexonly}
\subsection{Where the above idea came from}
This piece of information has been added on Aug 25.
I apologize I ``discovered'' it so late.
There is a detailed book about the problem, formulating the hypothesis
much better that ``I did'' in this Addendum. That's the original
source of the idea (my forgotten source summarizing the hypothesis and
giving that reference was
\wwwt{Clark 2003 -- Outdoor Lighting and Crime, Part 2}
{http://amper.ped.muni.cz/light/crime}):
\wwwt{Wiley, T. S. and Formby, B. (2000) \textit{Lights Out: Sleep, Sugar and
Survival.} New York, NY: Pocket Books (Simon and Schuster).}
{http://www.amazon.com/exec/obidos/tg/detail/-/0671038680/103-6415276-1739861?v=glance}
It's a pity their ideas seem to be so little investigated up to now.
Perhaps the book is not peer-rewiewed and so not considered as relevant
to scientists?
Clark summarizes the Wiley\&Formby hypothesis in these words: \\
\emph{``Year-round summer-length duration of daily
light exposure in humans and domestic animals appears to lead to
increased appetite, carbohydrate craving and fat storage in
preparation for the winter famine that never comes,
increasingly
leading to excess weight, obesity and consequent obesity-related
disorders and diseases.''}
%\thispagestyle{empty}
%\enlargethispage{1cm}
\section{Acknowledgement}
Apart from the Addendum, the above text is essentially the same as that
contained in the grant application. Just the English of the original
text had been poor. The current version is surely easier to read than
the first public one from Apr 1.
I'm much indebted to \wwwt{Bob
Mizon}{http://www.mizar-astro.freeserve.co.uk/} for correcting my text
from ``English'' into English, and to
\wwwt{Steve
Pauley}{http://www.pomona.edu/Magazine/pcmf99/32pcmf99.shtml}
(see ev. \wwwt{one of his lectures}
{http://www.mediasoft.net/macdowell/Downloads.htm})
for a suggestion
that the text \emph{should} be corrected.
\end{document}