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Get access to our School's on-line weather station data here
and technical details
of how we built it
Getting things in context:
 Over millions of years our rainforests evolved to play an important part in regulating our world's temperatures and climate, finally establishing an ecosystem in which we (amongst the world's youngest species) could emerge and survive. As we destroy our rainforests, pollute our environment and pretend we can take charge of creation, we place our human future at risk.
 Our planet is a complex system (which to us mortals may look chaotic) where everything is inter-dependent and interacts with everything else, including our solar system, the galaxies and all the phenomena it is part of. That is what our ancestors teach us about whakapapa (our connections with everything else and our respect for older species).
Nothing stands still. Our place is in a constant state of change where even small seemingly unimportant events can disturb the equilibrium and balance of life in massive ways which we cannot easily explain even by the best of western science and powerful computer modeling. Our world has billions of years of history measured in ages where large cyclic temperature changes took place and dominant species were routinely replaced.
 It would be very cheeky of us to think that by putting up a weather station at our kura we could prove whether serious climate change was happening today or not. If we could, it would likely be a last ditch call to man the lifeboats. It would be almost impossible for our school working alone to find a single simple or even a complicated way to influence it. (We refer to the Cynefin Framework video on U-tube which, though coming from an organisational perspective, can help us put our understanding of today's diverse climate change thinking into perceptive)
 Our aim is to take an indigenous science perspective which has for eternity gathered and passed on wisdom based on the observation of nature and its processes, in the form of oral stories, places and history. With the weather station we continue to look closely for lessons in the world around us, using today's technology to enhance and consolidate this wisdom. This we share and research on the web with all others who share our core values - We have a saying at our school. "We have no room around here for matapiko (stingy) gatekeepers" - those who hold all their information in their own back pocket and don't share it or test it against other minds and experiences.
TEMPERATURE: (normally shown on graphs as red - bold for outside temperature)
This measures how much heat energy something has. Something with a higher temperature tends to lose its heat energy to things with lower temperature, in three main ways (that we understand at present, but also magnetic fields also transfer energy(heat) - see electric toothbrush picture below)
(a) Conduction - when we touch something cold, heat is transferred from our hand to it
(b) Convection - when a gas or fluid passes by something - eg hot air rises to the top of a room
(c) Radiation - when heat is transferred through space - we feel a fire's warmth across a room
note: a dull black object transmits / absorbs heat radiation best - shiny white things reflect it
We measure a number of different temperatures:
 (1) TEMP - Outside air temperature (shaded in a white ventilated box 1200mm above ground level)
(2) Soil - Soil temperature 300mm below ground - it remains much more stable
(3) Black plate temp - heats up in the sun and gets colder than outside temp on clear frosty nights
(4) Classroom 1 temperature - allows us to see when heaters are left on after school
(5) eg Classroom 2 temperature - a portable sensor we can use for experiments
(6) eg Ponga Whare) temperature - another portable sensor (coming)
(7) Pole top Temperature - measured by the anemometer
(8)
Wind Chill Temperature - We calculate this from the anemometer pole top outside temperature and wind speed This indicates the extra risk we face from hypothermia in high winds particularly if we are wet
Frost: Caused by surface heat radiatd out into space on clear nights
 Getting the weather station taught us much about frost. Its readings showed us that the ground surface where the frost formed was losing its heat somehow, whilst the ground temperature 300 mm down was higher than zero and the pole top temperature was higher as well (have you seen horticulturists using helicopters to force warm air down to stop frost damage. We got the answer to this when we found some amateur weather station operators used what was called a "black body sensor in a jam jar" to measure night time cloud levels. From this we conclude that on a clear night the earth's surface radiates its heat out to cold space in all directions. When clouds or mist are present this radiated heat is reflected back. We therefore built a black body sensor for our station. (One of our local people who works a lot in the bush suggested that the nursery trees in the forest do this too - the underside of Ferns are silver! That is getting us thinking about suitable shade houses for winter crops). It reminds us that our old people knew something as we hear stories about them growing kumara and other food crops on the forest floor.
HUMIDITY: (Normally shown on graphs as blue - bold for outside humidity)
 This measures how much moisture (dampness) the air holds. As the temperature of air rises it can hold more water vapour. When it holds the maximum it can for that temperature it is said to have reached its "saturation" point . Our humidity sensors actually measure "relative humidity" which is a percentage of saturation ( eg 60% means the air is holding 60% of the total amount of water it could hold at the current temperature). This means that when the temperature rises (eg when the sun come out) the humidity goes down.
If we are all sealed inside a room (or a car) breathing out moisture (and particularly if we are wet) we find the air beside the windows reaches saturation point and starts condensing out as water - fogging things up. On miserable damp days, if we get some colder air from outside and heat it up (as do our classroom heat pumps) we can lower the humidity and so increase the comfort of our room.
The people of Te Urewera are referred to as the "Children of the Mist". Our rainforest traps a lot of moisture in the air around it, so when the temperature goes down at night our ancestor Hine Pukohurangi (The Mist Maiden) comes out to embrace our Maunga (Mountains) and valleys. That brings us to "The Dew Point", another temperature that our weather station calculates for us from the humidity and temperature readings. It tells how far the temperature must fall until the air is saturated and cannot hold any more vapour, so it starts condensing out as a fine mist that hangs around until the morning sun warms it up again. In that way, we are daily reminded that our ancestress Hine Pukohurangi is yet another kaitiaki that that protects us by regulating out of control surface freezing.
We measure four different Relative Humidity readings:
(1) HUMIDITY - Outside air humidity (shaded in a ventilated white box 1200mm above ground)
(2) Classroom 1 humidity - allows us to see when heaters are left on after school
(3) eg Classroom 2 humidity - a portable sensor we can use for experiments
(4)
eg Ponga Whare humidity - another portable sensor (coming)
(4) Dew Point Temperature - The temperature at which dew forms - calculated from above
RAINFALL (normally shown on graphs as light green)
Rain, hail and snow and snow works in a similar way to above. Clouds coming in from the across the sea arrive carrying a lot of moisture. When they hit the cold air above our forest clad mountains the water condenses out and falls as rain. If it freezes in the clouds it falls as snow, if the rain freezes on the way down, it falls onto us as hail.
We measure and accumulate data for this
RAIN / 1Hh - rain for last hour included in retained statistics and graphs
Rain / 24 hr - rainfall readings for the last hour
Historical rainfall records by month, year etc
On our weather page we point to the Metview 7 day rain forecast map. Be sure to check this if you want to go tramping in our area.
BAROMETRIC PRESSURE: (normally shown on graphs boldly in dark green)
As air gets warmer by getting heat from the sun, from the warmer ground or wherever other means, it expands in volume so it tends to rise. This means that the air pressure around the globe varies. It is measured as maximum at sea level reducing as our altitude increases and tending to zero at the outer edge of our earth's atmosphere.
The Barometric Pressure is actually the weight of the column of air above it divided by the area of the bottom of the column eg it has a unit of Kilograms per square metre or equivalent.
Our weather station adjusts the actual pressure measured at the altitude the station is at to an equivalent sea level reading so different results from different places and altitudes can be compared.
Generally speaking, if the barometric pressure is rising, then we probably have good sunny weather with clear skies coming. If it is falling, we can normally expect lots of clouds and rain.
WIND: (normally shown purple on graphs)
  If the barometric pressure is high at one place the air will tend to flow to other places where the pressure is lower. We experience this as wind. The Metrological Service publish a weather map where the lines "Isobars" join points where the pressure is the same. Where the isobay lines are close together, we can expect a lot of air movement, winds and storms.
In high pressure regions the wind tends to rotate clockwise in the Southern hemisphere and anti clockwise in the Northern hemisphere. We have anticyclones where the pressure is low that bring bad weather whereas in the northern hemisphere we hear about cyclones bringing storms and tornados.
Check how a weather map can show us how storms arise in the metservice videoclip
The Anemometer (Wind guage) is on the poletop 9 metres high and measures:
(1) hourly wind velocity
(2) wind gust velocity
(3) Wind direction
UV RADIATION: (normally shown bold yellow/gold on graphs)
Our weather station measures Ultraviolet levels using a sensor on the top of our pole to try to reduce its measurements being effected by ground level morning mist.
The UV Index tells us when the risk of skin cancer is highest, warning us to shield and protect ourselves from the sun. On the positive side it also is a source of Vitamen D
A Question our observations are asking us?
We are trying to understand what we observed on 5th and 6th of Sept 2009 (See example b below). Two cloudless days where we might have expected our black plate absorber and our UV detector to show a similar curve with both peaking at midday when the sun was highest. Instead, one day had a high UV peak around 10 am and the next had a high peak 3 pm. We are often reminded that "you can get sunburnt even when the sun is shaded by cloud". We wonder if this is due to the ozone hole ozone hole which rotates daily in a irregular fashion over Antarctica and is worst after the Polar winter. If our theory is right, then these peaks may be the UV that is coming through this hole when it lines up with the polar lights (Aurora) that are formed when solar winds interact with the earth's magnetic field high above the south pole. While UV from the Sun comes from the North, UV if it came through the oxone hole would come from the South direction. We could confirm this by watching how it was effected by clouds in either the North or the South, or by physically shading our UV detector from the North Sun.
For more science about this, see GLOBAL TEMPERATURE BALANCE MECHANISMS below.
SOME EXAMPLE DAYS:
(a) Cold frosty cloudless winter day
(b) Daytime UV peaks at different times - also the difference between frosty and snowy morning
 
GLOBAL TEMPERATURE BALANCE MECHANISMS (we are trying to relate our observations to these)
from http://oceanworld.tamu.edu/resources/oceanography-book/Images/greenhouseeffect.jpg
(a) Energy flow from the Sun that is absorbed by our Earth: - Global Heating Cycles
The FusedWeb information on our Sun tells us that the Sun has a very high core temperature of around 15,000,000 Degrees Centigrade which reduces as we move outwards to the photosphere which is the zone from which the sunlight we see is emitted, at around 6,000,000 Degrees Centigrade. This surface temperature can change widely due to surface storms, turbulence and sunspot action which seems to exhibit an approximately 11 year sunspot cycle.
This website also tells us about the massive magnetic fields that our sun has around it. It's solar storms boil off protons and electrons that reach the earth at velocities of 500 km/s. (Check out the NASA site about the Sun's magnetic field and also a report on the magnetic portals called Flux transfer events FTE that open between the sun and earth on an approximately eight minute cycle). That tells us that our earth really lives within the sun! Microvaves ovens also transfer heat energy to cook food.. maybe we can think of our earth as being within the sun's "Microvave Oven".
The Sun's magnetic fields (particularly in times of sunspots) react and interfere with the earth's magnetic field.  This may be another form of energy input to earth. (We already know changing magnetic fields can also transfer energy as we see an electromagnet in the base transfers energy to charge the the battery in the toothbrush without any physical connection). In our industry (eg aluminium production) we use this effect for induction heating. Induction heating is also used in some stove cook tops. If our earth sits within in a changing magnetic field then perhaps that may cause heat to be generated in its molten magnetic core with result that it could even be getting hotter rather than cooling down as we might think? See a video on "Tracking changes in the Earth's Magnetic Field" and a British Geological Survey Overview of the Earth's Magnetic Field) That shows that our earth has a daily magnetic cycle which is perhaps what the ozone hole movements show us.
The sun though very hot relative to earth's temperature, is however a small diameter radiator that only fills a small area of our earth's sky. In addition, its narrow rays reach us at a variable angle to the earth's surface so not all of it is absorbed. We can see this by the way our black plate (at our side of the earth) changes over the day in our daily heating cycle caused by the earth's rotating around its own axis. More still, as a result of our earth's orbit around the sun, the sun's angle is higher in summer and lower in winter. We see this annual cycle showing in the maximum, average and minimum temperature our black body sensor reaches each day over the whole year.
If we begin to understand the impact of our sun on our earth, perhaps we need to remind ourselves that that our solar system is but a tiny item in the much wider universe that makes up Ranginui (Sky and Heavens). Everything is connected by whakapapa like a family and inter-dependent.
(b) Energy flows from Earth into space - Global Cooling Mechanisms
The Earth's temperature is typically between minus 30 to plus 30 Degrees Centigrade and at very worst the temperature of space will probably be at absolute zero ( minus 273 degrees Celsius), so unlike the sun, the outgoing temperature difference is small. However, we wonder if maybe every tiny part of the surface of all objects on earth could be radiating its heat out to every part of space it can see that is above the earth's horizon. This we guess will happen 24 hours - day and night. We see this energy loss (cooling) as frost in the morning after clear cold nights. We wonder if a three dimensional forest icut down to make farmland for food or bio fuels production increases or decreases the heat energy our earth is able to radiate to cool itself. We hope to find this out somehow by some local climate experiments and observations around our rainforest Whirinaki: Te Pua o Tane .
Rainforests are important for global cooling and temperature regulation:
Our good friend and Whirinaki Rainforest patron Prof David Bellamy tells us that old growth forests with all their diversity help regulate the natural cycles of our world. We hope we can one day learn and demonstrate what he means by that. That matches what our ancestors tell us that Tane - god of the forests is the kaitaiki (guardian enabler and provider) of all life.
Also a blog by Folke Gunther (Sweden) "What are rainforests Good for" includes a NOAA- National Oceanic and Atmospheric Administration map of the world using satellite data that shows all that the cool spots are not just at the poles but include rainforest areas near the equator). Find out about the AVHRR - Advanced Very High Resolution Radiometer in satellites orbiting above the atmosphere that collect this data.
We have made connections with Ille Gebeshuber
a physicist doing research work in the Frazers Hill Rainforest site in Malaysia. Her work with biomimicry will likely help us better understand the role rain forests and in particular the leaves of its trees play in both absorbing , reflecting and radiating energy, to balance our world.
For a more academic investigation of rainforest effects on temperature see Eric Schneider and James Kay "Life is a manifestation of the second law of thermodynamics". Eric Schneider reminds us that whilst we rightly value a tree for its abilty to absorb CO2, the transpiration value of a tree is at least 100 times more important than its carbon storage value
. . A typical tree is pumping around 60 litres of water from its roots per day that it transpires (swets out) as vapour to the atmosphere, cooling the leaves in the process to stop them overheating and drying out. One litre of water converted to vapour requires an energy input of 332,000 Joules. (one joule per second equals an energy flow of one watt). The latent heat of evapouration in the tree, therfore produces around 230 watts of local cooling effect. If that tree covers say 10 square metres of the earth's surface that means its value is around 23 watts per square metre.
That moisture given off raises the humidity of the local atmosphere so that when the temperature falls below the dew point it condenses as clouds, mist, dew, frost snow or rain to give that energy out again to suppress overcooling and support life in the region around it, growing even more plants, trees and all the diverse species that grow around them. We call that the water cycle.
In winter we observe locally that frost occurs mainly on grassy frost flats, and on the branches of deciduous trees (often adjacent to streams running in valleys) where there is little chance for cold air to be dissipated by convection (air movement) or conduction of heat from the the ground (which is pumice and a good insulator). By comparison we less frequently see it on the native rainforest forest canopy treetops. We have some loose evidence which we will confirm next winter that frost is seen on the ground under some tree species but not others. In the book Whirinaki- To Save a Forest there is a diagram that helps explain the species movement in our forest and how new growth happens in the ecosystem it nurtures under its canopy.
At a deeper level we also are interested in what Paul Stamet tells us about the Mycorrhyzal fungi that supports rainforest life underground that is invisible to the naked eye
The Rainforest Alliance Website tells us that the world is cutting down around 13 Million Hectares per year (An area the size of the state of Louisianna, or half the area of New Zealand) and this contributes about 20% of the world's CO2 emissions. It's no wonder things are running out of control!
(c) The Delicate and Complex Living World Energy Balancing Act
Amidst all the other cycles effecting conditions on earth for life, including , geo movements, water, nutrients, oxygen, nitrogen, CO2, growth, greenhouse gases, ozone depletion, and adaptive interdependent species, we can be sure that the situation is complex.
From a traditional thermodynamics perspective, when the energy coming in is equal to that going out, we can think simplistically and remind ourselves that conditions may for a short while look stable. Our real world is much more complex than that with physical, chemical, biological (and even spiritual components). It's equilibrium (balance) is always changing.
 The difficulty we face is that the temperature of our planet and its climate is determined more by the difference between what is coming in and what is leaving, something we observe in our daily and seasonal cycles. For example if the average energy coming in from the sun was say 300 watts per square metre and what was leaving as radiation etc was say 300 watts per square metre, then a small (1%) change in the energy the sun was emitting, or a 1% restriction in the energy the earth could radiate or reflect back out to space as a result of greenhouse gas or cloud filtering / reflection ) may result in net temperature change effects on earth over time.
We have been told by a retired professor of engineering that the energy radiated by a hot body is proportional to the 4th power of its absolute temperature and that that means a small 1/4 % rise or fall in the sun's radiant temperature could result in a 1% rise or fall in the energy it radiates to earth. Conversely as a result of this, a 1/4 % rise in the earth's absolute temperature (around 293 degrees absolute = approx 0.75 degrees centigrade change), could result in a 1% increase in earth's outward outward radiated energy. (i.e. what we might see our black plate ( or our forest maybe) transmtting outwards on a clear cloudless night)
What no-one really understands yet is the wide range of highly inter-dependent natural regulating mechanisms that continually evolve in our universe in response to this. Our experiments with our energy capture box (photo) may help us understand just a little of this and also as a bonus help us make our houses more energy efficient
This complexity of course must not stop us from continuing to work with Papatuanuku and Ranginui (our Mother Earth and Sky Father) to help the long proven natural kaitiaki processes that they give us; playing our part by doing things that help them keep all in balance. The wisdom our ancestors have passed down to us in challenging stories are our guide, as is the modern scientific emphasis on Biomimicry. If we refuse to do this, the universe will find its own ways to deal to a selfish species prone to comforting itself in the short term by domination and polution; destroying the Mauri (Lifeforce) in the diversity of everything else around us that sustains life.
To do its part for all our futures, our iwi, Ngati Whare is pioneering a big project to restore Native forest that on previously milled land that is being returned to them under treaty settlements.
If you have suggestions, questions or feedback about this project, please email us
OTHER RESOURCES:
NIWA Educational information
Details of our weatherstation Project
How we have configured the Weather Station software we use
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