Category Archives: Peer Reviewed Article Review

Exxon knew

Exxon’s climate science was as good as that of government and academic scientists as long ago as the 1970s. They accurately predicted what was going to happen. And then they publicly lied and lied and lied about it. This is one of the most evil things ever done in the history of our world, because it affects every single one of the billions of people on the planet, and tens or hundreds or trillions yet to be born. And they knew exactly what they were doing. These people knowingly conspired to ruin a planet where every living being we know of in this universe live. And they did it for short term wealth and power, I guess.

On the basis of company records, we quantitatively evaluated all available global warming projections documented by—and in many cases modeled by—Exxon and ExxonMobil Corp scientists between 1977 and 2003. We find that most of their projections accurately forecast warming that is consistent with subsequent observations. Their projections were also consistent with, and at least as skillful as, those of independent academic and government models. Exxon and ExxonMobil Corp also correctly rejected the prospect of a coming ice age, accurately predicted when human-caused global warming would first be detected, and reasonably estimated the “carbon budget” for holding warming below 2°C. On each of these points, however, the company’s public statements about climate science contradicted its own scientific data.

Science

What climate tipping points are imminent?

According to a new Nature article (which this AP story does not link to directly), at 1.5 degrees Celsius of warming,

An international team of scientists looked at 16 climate tipping points — when a warming side effect is irreversible, self-perpetuating and major — and calculated rough temperature thresholds at which they are triggered. None of them are considered likely at current temperatures, though a few are possible. But with only a few more tenths of a degree of warming from now, at 1.5 degrees Celsius (2.7 degrees Fahrenheit) warming since pre-industrial times, four move into the likely range, according to a study in Thursday’s journal Science.

AP

The coral reefs will affect fishermen around the world in the very near future. The others, even though they are irreversible, may play out slowly even over centuries, according to the article.

how much food can we grow in cities?

Well, lots of salad apparently.

How Much Food Can We Grow in Urban Areas? Food Production and Crop Yields of Urban Agriculture: A Meta-Analysis

Urban agriculture can contribute to food security, food system resilience and sustainability at the city level. While studies have examined urban agricultural productivity, we lack systemic knowledge of how agricultural productivity of urban systems compares to conventional agriculture and how productivity varies for different urban spaces (e.g., allotments vs. rooftops vs. indoor farming) and growing systems (e.g., hydroponics vs. soil-based agriculture). Here, we present a global meta-analysis that seeks to quantify crop yields of urban agriculture for a broad range of crops and explore differences in yields for distinct urban spaces and growing systems. We found 200 studies reporting urban crop yields, from which 2,062 observations were extracted. Lettuces and chicories were the most studied urban grown crops. We observed high agronomic suitability of urban areas, with urban agricultural yields on par with or greater than global average conventional agricultural yields. “Cucumbers and gherkins” was the category of crops for which differences in yields between urban and conventional agriculture were the greatest (17 kg m−2 cycle−1 vs. 3.8 kg m−2 cycle−1). Some urban spaces and growing systems also had a significant effect on specific crop yields (e.g., tomato yields in hydroponic systems were significantly greater than tomato yields in soil-based systems). This analysis provides a more robust, globally relevant evidence base on the productivity of urban agriculture that can be used in future research and practice relating to urban agriculture, especially in scaling-up studies aiming to estimate the self-sufficiency of cities and towns and their potential to meet local food demand.

Earth’s Future

Water, energy, and fertilizer-efficient urban agriculture for some fresh produce in cities seems like a pretty good idea. Urban aquaculture seems practical to me. Growing enormous amounts of grain and protein does not at the moment, unless we are going to do it in high-rises under lights. That might be technological doable but farm fields out in the countryside are probably going to be more cost-effective for a long time to come, especially when the environmental costs are mostly not counted.

Even growing a few percent of our calories in cities might help to buffer any future food shocks by giving us extra time to react to them, and by reducing panic and economic disruption it could cause.

Universal health care would have saved lives in the pandemic

This article in PNAS estimates that a universal health care system in the United States could have prevented 212,000 deaths in 2020 alone. That is a big fraction of the total Covid deaths that year – I don’t have the number at my fingertips but total deaths over the whole pandemic (and caused by the pandemic) recently passed one million. I assume this does not count all the deaths from other causes that a health care system could have prevented. This sounds like a pro-life policy to me!

city biodiversity

This paper in Urban Forestry and Urban Greening suggests three ways to increase biodiversity in cities.

Consideration of the three key factors influencing biodiversity identified here (grassland extent, land-use in the surroundings, and management intensity) would provide the optimal options for maintaining city biodiversity. Protecting current urban grasslands from development and restricting construction in their surroundings, restoring city wilderness areas using urban spatial planning, and setting up butterfly-friendly management regimes (e.g., mowing in mosaic) could all be future options to help enhance biodiversity in cities.

Urban Forestry and Urban Greening

These sound like measures the average U.S. homeowner’s association will gleefully embrace (#irony).

weather control

Here is some new research on chaos theory and the so-called “butterfly attractor“. The idea is that by making small-scale interactions with the atmosphere, for example by speeding up or slowing down wind turbines, it might be possible to influence the development of extreme events. This is all theoretical and simulation-based at this point, but if it is true it would certainly be easier, more reversible and less risky than schemes such as releasing massive amounts of aerosols into the atmosphere.

climate migration modeling

Here is one new article on U.S. climate migration modeling, but I wasn’t able to access the conclusions. Going back to this 2020 article, which at least lets you stare at the pictures, major coastal cities like greater Boston, greater New York/New Jersey, Philadelphia, D.C., Jacksonville, Miami, and of course New Orleans are going to be in serious trouble by 2100. Population simulations show a lot of people just migrating inland a county or two, so maybe that is the form the evolution of our cities will take if sea level rise is relatively slow and gradual – protection of a few iconic/historical coastal areas perhaps, coupled with intensifying suburban sprawl in surrounding counties within the metro area? This sounds relatively undramatic, although bland and uninteresting and wasteful of both land and energy. Land use policies, such as zoning and green belts, could be overhauled now in anticipation, or we can just let this happen willy nilly.

It is not clear to me if these articles consider immigration, but I imagine there will be immigration pressure and we could also think about how to handle that in a smart way – which luckily our political system is just awesome at!

back to drugs and crime

Recently I said my thoughts on the relationship between violence and the drug economy were evolving. Well, here is a paper from Temple University showing evidence that a lot of violence is linked to the drug economy. They look at neighborhoods in Philadelphia that are similar across most variables other than drug activity, and show that the neighborhoods with more drug activity have more violence.

the Simon-Ehrlich bet

Paul Ehrlich has probably won his 1980 bet with Julian Simon in a number of parallel universes, according to this analysis:

Better lucky than good: The Simon-Ehrlich bet through the lens of financial economics

In 1980, Julian Simon and Paul Ehrlich bet on the future of natural resource prices as a vehicle for their public debate about mankind’s future. Simon ultimately won, and his victory has been used as evidence that innovation can offset material scarcity induced by human economic activity. But does the outcome of the bet truly suggest this? We recast the bet as a short-sale by Simon of Ehrlich’s portfolio of assets, allowing us to carefully analyze the choices made in the bet, including the resources chosen and their amounts and the period of the bet, conditioned on the information available to each man in 1980. We also investigate the role of randomness in the outcome of the bet. We find that, with careful portfolio construction, Ehrlich should win this bet more often than not, validating the age-old adage that it’s better to be lucky than good.

Ecological Economics

Does this mean that humanity as a whole is better off than we maybe “should be” on average? Hard to say.

How much ecological function can urban green space provide?

This is an important research question, I think, as the world becomes even more urbanized. Here’s a new study:

Vegetation Type and Age Matter: How to Optimize the Provision of Ecosystem Services in Urban Parks

As cities grow, urban greenspace assumes a more central role in the provision of ecosystem services (ESS). Many ecosystem services depend on the interactions of soil-plant systems, with the quantity and quality of services affected by plant type and age. The question, however, remains whether urban greenspace can be included in the same ecological framework as non-urban greenspace. Our previous studies have contributed towards filling this knowledge gap by investigating the effects of plant functional type (evergreen trees, deciduous trees and lawn) and plant age on soil characteristics and functionality in urban greenspace, offering also a comparison with non-urban greenspace. A total of 41 urban parks and five non-urban forest sites within and adjacent to the cities of Helsinki and Lahti (Finland) were included in this project. Path analyses presented in this contribution, combined with a synthesis of previous findings, offer strong evidence that urban greenspace functions similarly to non-urban greenspace. In particular, plant functional types lead to soil environmental modifications similar to those in non-urban ecosystems. Therefore, vegetation choice upon park construction/implementation can improve the quality and quantity of ESS provided by urban greenspace. However, although vegetation modifies urban greenspace soils with time in a fashion similar to non-urban greenspace, the vegetation type effect is greater in non-urban greenspaces. To conclude, our synthesis of previous studies provides science-based guidance for urban planners who aim to optimize ESS in urban greenspaces.

Urban Forestry and Urban Greening

Ecosystem services and ecological function are not exactly the same thing. Ecological function just is. Ecosystem services are what ecological functions do for people, and fit into the mainstream economic analysis framework. Part of the issue in studying this, I think, is scale. If you look only at one site, block, or park in a city, you might conclude that ecosystems services are negligible or un-measurable. If you look at the entire network and how it is connected, you might conclude that the effects are measurable and that there are policy and design choices that could make them better.

Biodiversity is something else again. More biodiversity is not always better, if it consists of more species of rats or coronaviruses, for example. But biodiversity may be a reasonable proxy measure for how the structure of a designed urban ecosystem translates to ecological function. This is useful if ecological function itself turns out to be difficult to measure. And I think the most useful measures might be biodiversity of animals such as insects (bees, butterflies) and birds. Because the plants in urban areas are mostly the ones that people put there. Biodiversity of plants can be improved through design choices, which is a good thing but in measuring that you are largely measuring inputs to the system rather than the resulting state of the system. Measure the animals, and you are measuring the resulting state of the system.

Measuring things that flit and flutter around might seem daunting. Well, you could try to do it with cameras and image processing of some sort. Or if you are interested in insects you can focus on larva, aka caterpillars. Tracking down bee and wasp nests seems a bit more risky, and you might also have a public relations problem trying to explain why more bee and wasp nests would be a good thing. But caterpillars don’t move fast, so trained people should be able to cordon off an area and find and identify them periodically. Let’s say you did this once a week for a year at several defined points in an urban area, especially if land use changes are occurring (or maybe some places they are occurring and some places they are not occurring.) Doing the same thing in nearby forests and/or farm fields might also add worthwhile data. Now you can do some data analysis and modeling, and maybe figure out design or policy choices that would help the little critters while also benefiting or at least not pissing off people or costing them any money. If you want to fund my half-baked research proposal, let me know.