<p>When defining an area average of sea ice thickness, it is important to distinguish between an average taken over an ocean area</p>

<p>$$h_1 = \sum \frac{\text{sea ice thickness (in area)}}{\text{area}_\text{ice} + \text{area}_\text{water}}$$</p>

<p>and an average taken over the ice covered area</p>

<p>$$h_2 = \sum \frac{\text{sea ice thickness (in area)}}{\text{area}_\text{ice}}$$</p>

<p>The notations $h_1$ and $h_2$ are mine. I've seen both quantities referred to as “effective ice thickness”. I might go with <a href="http://dx.doi.org/10.1175/JCLI-D-13-00301.1" rel="nofollow noreferrer">Holland et al 2014</a> and call $h_1$ “effective ice thickness” and $h_2$ “average ice thickness”.</p>

<p>As an example think of a multi-category sea ice model: Let's say an ocean grid cell has a sea ice concentration of 50 %. Thus 50 % of the ocean grid cell is covered by water. The other 50 % of the grid cell is half-filled with 50 cm thick ice and half filled with 30 cm thick ice. For this case $h_1$ and $h_2$ would be 0.2 m and 0.4 m:</p>

<p>$$\begin{align}
h_1 &amp;= 0.5 \times 0 \text{m} + 0.25 \times 0.5 \text{m} + 0.25 \times 0.3 \text{m} = 0.2 \text{m} \\
h_2 &amp;= 0.5 \times 0.5 \text{m} + 0.5 \times 0.3 \text{m} = 0.4 \text{m} 
\end{align}$$ </p>

<p>Both variables can be useful. As I have seen conflicting names, I am a bit puzzled with the naming for $h_1$ and $h_2$. <strong>What are the standard names for $h_1$ and $h_2$ used in the sea ice community?</strong></p>

CC BY-SA 3.0
2015-10-23T17:59:15.540Z
This particular Google search should help you. https://www.google.com/search?q=%22average+sea+ice+thickness%22+%22effective+sea+ice+thickness%22
Eubie Drew
<terminology><sea-ice><cryosphere>
Naming convention for sea ice thickness per unit area of ice or ocean
BHF
# Naming convention for sea ice thickness per unit area of ice or ocean

(Asked by: username_0 on 2014-04-18)

When defining an area average of sea ice thickness, it is important to distinguish between an average taken over an ocean area

$$h\_1 = \sum \frac{\text{sea ice thickness (in area)}}{\text{area}\_\text{ice} + \text{area}\_\text{water}}$$

and an average taken over the ice covered area

$$h\_2 = \sum \frac{\text{sea ice thickness (in area)}}{\text{area}\_\text{ice}}$$

The notations $h\_1$ and $h\_2$ are mine. I've seen both quantities referred to as “effective ice thickness”. I might go with [Holland et al 2014](http://dx.doi.org/10.1175/JCLI-D-13-00301.1) and call $h\_1$ “effective ice thickness” and $h\_2$ “average ice thickness”.

As an example think of a multi-category sea ice model: Let's say an ocean grid cell has a sea ice concentration of 50 %. Thus 50 % of the ocean grid cell is covered by water. The other 50 % of the grid cell is half-filled with 50 cm thick ice and half filled with 30 cm thick ice. For this case $h\_1$ and $h\_2$ would be 0.2 m and 0.4 m:

$$\begin{align}
h\_1 &= 0.5 \times 0 \text{m} + 0.25 \times 0.5 \text{m} + 0.25 \times 0.3 \text{m} = 0.2 \text{m} \\
h\_2 &= 0.5 \times 0.5 \text{m} + 0.5 \times 0.3 \text{m} = 0.4 \text{m}
\end{align}$$

Both variables can be useful. As I have seen conflicting names, I am a bit puzzled with the naming for $h\_1$ and $h\_2$. **What are the standard names for $h\_1$ and $h\_2$ used in the sea ice community?**

**Tags:** terminology, sea-ice, cryosphere

> **Comments:**
> **username_1**: This particular Google search should help you. https://www.google.com/search?q=%22average+sea+ice+thickness%22+%22effective+sea+ice+thickness%22  

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## 0 answers

