Student Worksheet

Thought starter: Albert Einstein said, "We cannot solve our problems with the same thinking we used when we created them".

Part A: Sea-levels on the Rise

1. Watch the Sealeaf project video below.

2. Share with a partner 'what you like' and 'what puzzles you' about the Sealeaf project.

Sealeaf - Short Cut (https://vimeo.com/58332025)

Many observations show that the ocean has been changing over the last several decades. One aspect of this change is ocean warming, which results in an increase of ocean volume through thermal expansion. There has also been addition of water from glacier and ice sheets, as well as changes in storage of water on or in the land (e.g. retention of water in man-made dams and extraction of water from aquifers). Together, these factors result in the sea level changing. This graphs shows in global mean sea level from 1880-2012.

For more information you may like to read the CSIRO's Sea Level page.

Part B: Calculating Sea-levels

Use this graph to help answer the following questions:

Question 1

e. Which words apply to the graph: linear, non-linear, increasing, decreasing?

f. In your own words, describe what the graph shows has been happening to global sea levels since 1880.

g. What environmental factors might be contributing to the 'up and down' of the blue line.

Since 1880, mean sea-levels have been recorded at every year. We can see that, in general, the levels seem to be increasing but there is a lot of fluctuation! For the purpose of this analyses, let's use the graph to estimate the sea levels for 10 years...

Year	GMSL (mm)
1880	0
1890	20
1900	35
1910	35
1920	48
1930	50
1940	70
1950	85
1960	115
1970	120
1980	140
1990	160
2000	180
2010	215

Sampling the data this way can give us a general idea how the levels are trending. Often, points are labeled to make descriptions or tasks simpler. On the above graph, we could say that the coordinates for point a are (1880, 0), the coordinates for point b are (1890, 20) and so on...