True polar wandering and the weight of water

What has changed
Not the weight itself,
But wait –
Extracted basin
Too full
still.

Keep the name
On the edge of the dam wall,
Etching and drying
Year and
Last permission.
Somewhere in a gear
expand
balance
Forgotten.

Axis not
Reason for request –
follow
What gathering:
Lakeside,
The stone crosses
Old route
Wear
A new turn.

Don’t move forward.
Not back.
only
Loose.

The poem was inspired by recent research that found that from 1835 to 2011, water in the reservoir was blocked, moving the Earth’s axis of rotation more than half a meter.

In the 20th century, human activities not only changed the surface of the earth, but also changed its physical balance. Large dams and reservoirs are known as artificial water storage, moving a lot of water somewhere. These changes in mass affect the earth in subtle ways. Even small changes can affect how the earth rotates. This process is called true polar wandering or TPW. Understanding TPW is crucial to tracking long-term changes in Earth’s system. It also helps us explain signals related to climate change. However, until recently, it was difficult to assess the impact of dam construction. Older records are often incomplete or inconsistent.

The study used a newer global database that included nearly three-quarters of recorded water storage storage from 1835 to 2011. With this improved data set, the researchers calculated how artificial reservoirs affect the Earth’s axis of rotation over time. They found that the TPW path caused by dam construction was more complex than previously suggested estimates. It also moves in different directions. Although some data are still missing, studies show that these gaps may not change the main results. Therefore, the study is more accurate in how dam construction shapes the movement of the earth. This also makes it easier to distinguish this effect from other effects such as melted glaciers and ice sheets. Together, these insights show how human actions continue to leave physical traces on Earth.