Columbia University's Earth Institute publishes articles on climate, energy, water, and sustainability topics such as cement emissions, fog harvesting, and planetary boundaries.
HN commenters cite it for facts on cement's share of CO2 emissions and for water scarcity pieces, such as the Middle East's drying aquifers.
I'm surprised no one has commented on the amount of fresh water we use to produce ethanol, particularly ethanol derived from corn.
Water is needed to grow the corn and also in processing it.
"The amount of water it takes to produce ethanol varies according to how much irrigation is needed for the corn, particularly since row crop agriculture for corn is the most water consuming stage of ethanol production. In Ohio, because of sufficient rainfall, only 1% of the corn is irrigated while in Nebraska 72% of the crop is irrigated. It takes 19 gallons of water to produce a bushel of corn in Region 5, 38 gallons in Region 6, and 865 gallons in Region 7. The Baker Institute estimates that producing the corn to meet the ethanol mandate for 2015 will require 2.9 trillion gallons of water.
Most of this irrigation water is drawn from groundwater aquifers in a region that is already water stressed. Conflicts over water allotments have occurred in Kansas and Nebraska, and the Ogallala Aquifer, which lies under the Great Plains and supplies 30% of the nation’s groundwater for irrigation, is in danger of running dry.
Growing corn also requires a great deal of fertilizer, and extensive use of nitrogen fertilizer and pesticides is having severe impacts on water quality now. Fertilizer laden runoff into streams in the Midwest makes its way to the Mississippi River, and eventually contributes to the eutrophication (when algae bloom, then die, depleting the area of oxygen and suffocating…
Climate disasters should get a boost because it can lead to war and water scarcity. Consider India and Pakistan. Both of them greatly depend on water from Himalayan glaciers, a source that is rapidly declining due to climate change.
They could end up at war over this, and they both have nukes. They have relatively small stockpiles with relatively small nukes so you might not think this would be a big deal globally--a terrible tragedy still but just a regional tragedy.
Not so. Here is an article [1] and a paper [2] that looks at global consequences of India and Pakistan exchanging 100 nukes (about 1/3 of what they have) each the size of what the US used on Hiroshima at the end of WW II and directed at major population centers in the two countries.
Based on the amount of combustable material in those areas, they estimate that the resulting firestorms would put 1.8 Tg of soot aerosol into the upper atmosphere.
Climate models say the effect of that would be a 1.8℃ temperature reduction and an 8% precipitation reduction lasting for many years.
They then apply state of the art crop models to predict the effect on agriculture. The result would be a serious reduction in yield which would be largest in temperate regions of the US, Europe, and China for 10-15 years.
There would be food shortages and famine in rich countries that normally do not see famine. That can be pretty destabilizing and it is not a stretch to imagine some first world countries might go to war over…
You’re right that I should have been citing my sources. I’ve been largely relying on the book Apocalypse Never by Michael Shellenberger. It’s well worth reading.
The (decade old) source you provided for energy subsidies appears somewhat dishonest, as the date ranges appear cherry picked. Why is it that the source only looks at nuclear subsidies up until 1999, while subsidies to other energy sources are considered through 2009?
The choice of units in this source is also odd. What have the subsidies been in terms of energy output? At its peak, nuclear was producing some 16-20% of US power. I imagine normalizing on a $/MWh basis could paint a different picture.
Looking at a more recent source [0], it appears that recent nuclear subsidies have been marginal and are far outpaced by renewable subsidies. If we consider prior subsidies a sunk cost, it doesn’t necessarily make sense to subsidize a new, less environmentally friendly, source of energy when our best in class is already excellent.
[0] https://blogs.ei.columbia.edu/2019/09/23/energy-subsidies-renewables-fossil-fuels/
Pretty much the same as me. Although biking is quite natural in the Netherlands and I commute to work by bike like many others here.
The only thing you might need to look out for are the claims for local, small producers.
http://freakonomics.com/2011/11/14/the-inefficiency-of-local-food/
http://blogs.ei.columbia.edu/2012/09/04/how-green-is-local-food/
+ There are economies of scale.
+ There are also people against genetic engineering even if it would reduce pesticides or other pressure on the environment tremendously.
+ Food safety might be more efficiently regulated in a centralized manner.
+ Old-fashioned greenhouses might have large yields and might be properly scaled to reduce costs per produced crop as well as support recycling systems for CO2 and other "waste" products.
In other words, the situation around food seems more complicated than just "buy local".
I found the terms confusing so looked them up. Does this look right to you?
Glacier: Large ice masses created by snowfall that has transformed into ice and compressed over the course of many years. Ice sheets, ice streams, and ice shelves are a few types of glaciers. [2]
Ice Sheets: Freaking huge glaciers
Ice Cliffs: the vertical edges of an ice sheet. Like a rock cliff but made of ice.
Ice Shelf: the "hanging chad" of the ice world. Chunk of an ice sheet that extends out over the ocean (nice diagram in source below) [1]
Sea ice: Frozen seawater, floating on the ocean. Not made from snowfall.
Iceberg: Ice floating on the ocean, chunk of an ice sheet/ice shelf
[1] Helpful:
http://www.antarcticglaciers.org/glacier-processes/glacier-types/ice-shelves-sea-ice-icebergs/
[2] https://blogs.ei.columbia.edu/2018/02/05/glaciers-ice-sheets-polar-ice/
> I've read this a few times and I keep reading it the same way "We produce waste that can be used to feed animals as a bitproduct of producing feed for animals?
My point is that we don't need to produce feed for animals, they do fine just on pastureland.
The way we currently raise grains is problematic enough as it is, requiring huge fertilizer inputs[1] which require petrochemicals. Eating grains is not a sustainable alternative - if we raised grains for human food, might as well feed animals and get some steaks out of it.
>And tons more cleared grassland.
The great plains did not need to be cleared. They were perfect pastures for grazing animals, not the modern monoculture of grains.
[1] (we're running out of phosphorous http://blogs.ei.columbia.edu/2013/04/01/phosphorus-essential-to-life-are-we-running-out/)