Precipitation may decrease, and that needs to be taken into account in the scenario planning. There are climatologists on the California Department of Water Resources staff, so my guess is that they are looking at this. I also think they are very worried because they do take this into account...........................................There may also be more extreme large rain events in future, as is happening in many places in the world. If this is the case, its important that we can guide those large storms into the aquifers.
I think you need to ask Helen Dahlke another very important set of questions, because this interview did not provide any projections as to how much the timeline could be changed from the current trajectory of only 20 years left of groundwater in CA! We need multiple alternative projections under a variety of mitigated scenarios. What's the best case senario? How much time is left if we do all we can? How about how much time is left under a reasonably altered scenario? Given the history of ineffective action in this state, I'm affraid that's not much.
Each year we have some excess water from the huge rains. Half of Californias water comes from large atmospheric river dumps. If we can guide some percentage of that into the aquifers that would be helpful.... If we get southern california to recycle their stormwater instead of having it runoff to ocean, then there will be a lot more water in central valley to replenish aquifers there.... If we create more wetlands in central valley eg. aquaculture wetlands, then that will help restore the small water cycle so that there is more rain in the Sierras. That extra rain can be used to help restore the groundwater. If we create a net increase in continental water each year rather than a net decrease, then we will have more water for groundwater replenishment
I am definitely interested in these statements, especially the stormwater loss to the ocean here in coastal So. Cal. But what I am looking for is a rigorously quantitative analysis of these statements. We will need that sort of scientific, numerical analysis to have our concerns taken more seriously. I have emailed Helen Dahlke my question, and I think you should interview her again to try to get her to think more quantitatively about the problem. Keep in mind, for example, that only a small fraction of California is coastal, and therefore a lot of the inland precipitation is probably making it's way to the aquifers already. I'm concerned that the total annual percipitation--especially during drought phases--may not be enough even if we do everything you are saying. But without numerical calculations, even just "napkin" calculations, this is all just talk--as the late English physicist David MacKay used to say--"hot air". I did a few calculations myself as to how much more water California farmland could hold with every 1% average increase in soil organic content. Billions of gallons annually, although only some is lost to evaporation and perhaps a lot making it down to aquifers anyway. And if we can get a hydrologist such as Helen Dalke to run some calculations under a reasonable variety of assumptions (ie. a variety of combinations of the scenarios you described) then we would have a much more credible, realistic assessment with an ability to understand how much can be accomplished at what cost.
See, for example right here: https://t.co/Z4iAPBskPi
It's all talk, with no quantitative treatment or comparative analysis of Cameron taking these actions vs not.
Here is Helen Dahlke's scientific paper on the recharge with data https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2018WR024019
Also the California Department of Water Resources have crunched numbers and done scenarios for groundwater recharge. See this link https://water.ca.gov/programs/all-programs/flood-mar
California has now passed a law on groundwater called SGMA, which also helps fund communities to recharge their groundwater https://water.ca.gov/programs/groundwater-management/sgma-groundwater-management
Precipitation may decrease, and that needs to be taken into account in the scenario planning. There are climatologists on the California Department of Water Resources staff, so my guess is that they are looking at this. I also think they are very worried because they do take this into account...........................................There may also be more extreme large rain events in future, as is happening in many places in the world. If this is the case, its important that we can guide those large storms into the aquifers.
I think you need to ask Helen Dahlke another very important set of questions, because this interview did not provide any projections as to how much the timeline could be changed from the current trajectory of only 20 years left of groundwater in CA! We need multiple alternative projections under a variety of mitigated scenarios. What's the best case senario? How much time is left if we do all we can? How about how much time is left under a reasonably altered scenario? Given the history of ineffective action in this state, I'm affraid that's not much.
October 12...of which year????
2022. I recorded it last week.
Each year we have some excess water from the huge rains. Half of Californias water comes from large atmospheric river dumps. If we can guide some percentage of that into the aquifers that would be helpful.... If we get southern california to recycle their stormwater instead of having it runoff to ocean, then there will be a lot more water in central valley to replenish aquifers there.... If we create more wetlands in central valley eg. aquaculture wetlands, then that will help restore the small water cycle so that there is more rain in the Sierras. That extra rain can be used to help restore the groundwater. If we create a net increase in continental water each year rather than a net decrease, then we will have more water for groundwater replenishment
I am definitely interested in these statements, especially the stormwater loss to the ocean here in coastal So. Cal. But what I am looking for is a rigorously quantitative analysis of these statements. We will need that sort of scientific, numerical analysis to have our concerns taken more seriously. I have emailed Helen Dahlke my question, and I think you should interview her again to try to get her to think more quantitatively about the problem. Keep in mind, for example, that only a small fraction of California is coastal, and therefore a lot of the inland precipitation is probably making it's way to the aquifers already. I'm concerned that the total annual percipitation--especially during drought phases--may not be enough even if we do everything you are saying. But without numerical calculations, even just "napkin" calculations, this is all just talk--as the late English physicist David MacKay used to say--"hot air". I did a few calculations myself as to how much more water California farmland could hold with every 1% average increase in soil organic content. Billions of gallons annually, although only some is lost to evaporation and perhaps a lot making it down to aquifers anyway. And if we can get a hydrologist such as Helen Dalke to run some calculations under a reasonable variety of assumptions (ie. a variety of combinations of the scenarios you described) then we would have a much more credible, realistic assessment with an ability to understand how much can be accomplished at what cost.