You are Here: Home

# Geography Question watch

1. In relation to a woodland micrclimate:

1) What is the transmission coefficient?

2) How is this calculated?

3) Any other information?

I'm baffled and can't find any information anywhere.
2. I think that the transmision co-efficiant is something related to the albedo(reflectifness) of the woodlands. Infra red readiation from the sun will be blocked to a certain extent by the foliage of a woodland meaning that in summer the woodland is often cooler than the open ground. The transmission coefficiant is something like the percentage of light absorbed and there is a formula I have seen before. This may be wrong though as it is a vauge memory.

hope this helps
3. Yes kind of, any idea on the formula??
4. I will try and get the formula for you at school tomorrow as a print out and i will put some info on this thread including the calculations. We have a database with quite a bit on microclimates.
5. (Original post by tom c)
I will try and get the formula for you at school tomorrow as a print out and i will put some info on this thread including the calculations. We have a database with quite a bit on microclimates.
Yeah that would excellent, look forward to it
6. Here is some general info:

solar radiation on average trees reflect around 30% of solar radiation falling on them but sunflecking takes place where there are gaps in the canopy and patches of sunlight reach the floor, for example in a beech or oak woodland. the transsmission of light is highly dependant on the type of tree (eg 50% oak in winter and 20-30% in summer where leaves block). For a spruce forest it can be as little as 5% all year round. Clearly this has an impact on the temperatures and ground , herb and shrub layers (serveys of species % and diversity possible). The light meter results are best converted into a transmission coefficiant, i.e. the ratio between the light level at a sample point inside the woodland (L1) and then recording outside in the control (L2), therefore TC= L1/L2. Then isopleth maps can be constructed and analysed to show variation. these results can be related to photographs taken vertically upwards and gridded to determine the relative proportion of dark (i.e. canopy) and light areas. Correlations using rs between TC and % canopy can be made for the sample points in each quadrat.

hope this helps.
7. Thats just what i wanted, thanks very much, really appreciated!

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: April 19, 2004
Today on TSR

### University open days

1. University of Cambridge
Wed, 26 Sep '18
2. Norwich University of the Arts
Fri, 28 Sep '18
3. Edge Hill University
Faculty of Health and Social Care Undergraduate
Sat, 29 Sep '18
Poll

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE