Will This Float Your Boat - 7

Fig. 1 Antarctica melt zones (click to enlarge)

Following some new research, I have expanded the scope of the C++ Sea Level Calculation Program.

It now includes all of Antarctica, not just W. Antarctica, as you can see from the graphic to the left.

For consistency I have also updated the dimensions of the four zones of melt for both Greenland (Fig. 3) and Antarctica (Fig. 1).

Since Greenland is the location of 75% of current ice melt that contributes to Global Sea Level Rise (SLR), and since Antarctica is only responsible for 25% currently (primarily from W. Antarctica), E. Antarctica can seem insignificant.

That will change over time, as the graphs later on in this post will show, because, among other things E. Antarctica contains enough ice that if it all melted, it would cause SLR of 212.58 feet all by itself (see Fig. 4).

Lucky for us it is not melting much now, so we focus on W. Antarctica and Greenland in terms of ongoing SLR.

The updates to the software are for not only improved accuracy, but for long term

Fig 2. Detail (click to enlarge)

projections to prove some long term points.

Furthermore, W. Antarctica and E. Antarctica are somewhat arbitrary descriptions.

For example, W. Antarctica in reality includes the Antarctic Peninsula, however, SLR is often calculated separately for the two.

Add to that the fact that some ice shelfs currently melting cross the E. W. boundary, such as the Ross Ice Shelf and the Fimbulisen Ice Shelf --both technically located in both W. Antarctica and E. Antarctica (see Fig. 2).

So, I use the designations "coastal, inland 1, inland 2, and no melt" in the software design melt zones of ice (see Fig. 1 and Fig. 2).

Fig. 3 Greenland (click to enlarge)

After all, the concern is ice melt going into the oceans over a given span of time, and the SLR results of that melt.

The zones have been unified (coastal, inland 1, inland 2, no melt) as have the colors (blue, cyan, yellow, red-orange).

Now, all ice melt on the planet is included in the SLR calculations.

The difficult issues are determining the percentages of ice in each zone of Greenland and Antarctica.

Add to that the difficulty in determining the rate of acceleration of each of those zones over time.

The difficulty is exacerbated by the back that those values, amount of ice in each zone and percentage of acceleration of melt, are in constant flux.

Fig. 4USGS Data (click to enlarge)

That is, they are naturally constantly changing from year to year.

So, the software numeric assumptions must change from time to time to keep up with it.

The volume of ice, potential SLR, and percentages are shown in Fig. 4, figures which change too, although the major percentages in no melt zones are changing very little at this time.

Later on today I plan to post some graphs with short term and long term projections using the changes discussed above.

The previous post in this series is here.