Pemba wrote: ↑
Fri Nov 08, 2019 2:48 pm
Matteo V wrote: ↑
Thu Nov 07, 2019 4:03 pm
Pemba wrote: ↑
Thu Nov 07, 2019 3:16 pm
I think there is evidence of harm: land getting flooded for instance. But that happens somewhere far away mostly.
This is another piece of propaganda that "climate change enthusiasts" are constantly caught presenting in a very unscientific way (actually they just lie about it). They specifically and intentionally confuse sea level rise with erosion. Erosion is a constant. It will not stop, even when sea levels drop. Any land near sea level will be eroded by wave action up to the maximum height of waves that come in contact with it. Sand and dirt erode at extremely high rates, but are replaced by flooding at high rates too. This is how river deltas form. Dams that hold back sediment prevent deltas from replacing newly eroded soil/sand with new material from upstream. But many places exist around the globe that have naturally lost their means of sediment replenishment long ago. These places are eroding, and have been eroding for sometimes millions of years. To present them as the victim of a single centimeter of sea level rise, is a blatant lie.
Rising seawater levels would obviously increase erosion. But there would be increased deposition as well. Are you saying that erosion is added to the equation but deposition isn't ? I think both would in many cases be very difficult to accurately predict.
Deposition downstream of materials is certainly affected by human activities such as:
1. Dams - essentially huge silt ponds until the lake is filled with sediment and has a high rate of flow from inlet to outlet.
2. Irrigation - reduces flows that actually make it to the river delta - just look where the Colorado River in the US empties in to Gulf of California (Sea of Cortez)
3. Erosion prevention measures and dredging for channelization - dump large amounts of what would have been new land (sediment), into deeper areas of the ocean or pile it up high on sand bars that normally would not have exceeded the high water line of the natural flow of a river.
Thus, very few places have anywhere close to historic sediment deposition, while some rivers now technically have no sediment flow into the river delta/ocean. And specifically, more rainfall into a reservoir is likely destined to be used for increasing irrigation, so it will never carry any sediment into the ocean for deposition.