L2 - Observational Techniques

Question 1

What is the traditional method used to measure Air Temperature?

Answer 1

A Stevenson Screen

Question 2

What are the 3 key components of a Stevenson Screen?

Answer 2

1. Mercury in Glass Thermometer
2. Thermograph
3. Dry Bulb and Wet Bulb

Question 3

At what time is the Stevenson Screen measured to give the daytime maximum and nighttime minimum?

Answer 3

0900 and 2100 (Local Time)

Question 4

How accurate is a traditional Stevenson Screen?

Answer 4

+/- 0.1 DegC

Question 5

What must be the same for all Stevenson Screens across the world?

Answer 5

They must be set at the same height from the ground

Question 6

What is the accuracy of some of the modern day automated Stevenson Screens?

Answer 6

+/- 0.01 DegC

Question 7

Why is it difficult to measure air temperature at sea?

Answer 7

The screens are at varying heights

Question 8

Who sets the standardised coding system for airfield observations?

Answer 8

The WMO

Question 9

Why are feet used for measuring cloud heights in airfield observations?

Answer 9

To avoid confusion with horizontal flying distances

Question 10

Why is deploying a Radiosonde at Sea difficult to get right?

Answer 10

Because as soon as it moves in a downwards direction it stops recording

Question 11

What are the 4 parameters that can be measured by a Radiosonde?

Answer 11

1. Temperature
2. Conductivity
3. Height
4. Upper Wind Speed

Question 12

Give 3 factors that require accurate sea temperature measurements?

Answer 12

1. Climate Change
2. Marine Ecosystems
3. El Ninõ

Question 13

Below what depth is data sparse in the oceans?

Answer 13

450m

Question 14

What is a Sea Bucket?

Answer 14

A mercury and glass thermometer in a neoprene tube that is lowered 1m below the sea surface

Question 15

Why are Engine Intake Temperatures potentially inaccurate?

Answer 15

You don’t always know the true position of the thermometer relative to the engine – the engine heat could be impacting the recording

Question 16

What is the difference between a Bathy and CTD measurement?

Answer 16

Bathy only measures temperature and depth, whereas, CTD also measures conductivity

Question 17

What is an XBT probe?

Answer 17

A Bathy ThermoGraph

Question 18

Give 5 Visual Observational Techniques

Answer 18

1. Visibility
2. Cloud Types
3. Counting
4. Identification
5. Ships of Opportunity

Question 19

Give an example of Ships of Opportunity?

Answer 19

Opportunistic MMO on a cruise, especially in the Arctic or Antarctic

Question 20

What has to happen to the opportunistic visual observations?

Answer 20

They have to be merged with systematic data

Question 21

What is ODAS?

Answer 21

Ocean Data Acquisition System - Part of The Moored Data Buoys

Question 22

How can the Public help with observations?

Answer 22

Home Weather Systems and giving observations that serve the UK Met Office

Question 23

How many buoys are free floating as part of the Argo System?

Answer 23

~3000

Question 24

What is SOFAR? and What is it used for?

Answer 24

Sonar Fixing and Ranging

Used for Deep Ocean observations

Question 25

Where is the main Munro Tide Gauge in the UK located?

Answer 25

Newlyn, Cornwall

Question 26

What are tidal measurements/curves used for?

Answer 26

Calculating residuals and HW and LW etc.

Question 27

What is GLOSS

Answer 27

The Global Sea Level Observing System

Question 28

Where is the UK National Tide and Sea Level Facility located?

Answer 28

At the NOC in Southampton

Question 29

Give the 3 types of data that can be collected by a towed profiler

Answer 29

1. Physical 2. Biological 3. Chemical

Question 30

Give 5 emerging issues associated with observing the marine environment

Answer 30

1. Data Sparse Regions 2. Increasing role of Technology -- Some Parameters cannot be easily automated 3. Lack of Standardised Methodologies 4. Lack of understanding regarding the sources and impacts of errors 5. Is there a lack of established communication of data?