That banks the river for which it's named

Rivers are special. These ribbon-like bodies of water cut through topography, shaping and shifting the landscape around them.

rivers begin where they end
if 1 considers rain + jet stream winds
look deeper into grainy sands
the sublimation from the wind-swept lands ever reach sea — Jordan, Sound Furies

My partner and I have always been drawn to rivers and try to live or be near them. We currently reside quite close to the great Hudson River (~500 km long), where we can amble through Riverside Park and enjoy the views. We are so obsessed with rivers that we made a double album as the Sound Furies dedicated to rivers, entitled “Tributaries.” One of my favorite songs from the album is Columbia.

We are not alone in our obsession with all things river. There are many songs inspired by rivers in the archives of rock-n-roll. Al Green just wanted someone to take him to the river. Jimmy Cliff had many rivers to cross. Joni Mitchell longed to have a river to skate away on. Sam Cooke was born by a river. Tina fearlessly rolled on a river (thanks for the original CCR). I could go on and on, but I think you get the point. Rivers mean something to many of us.

It is not just music. There are a plethora of movies about rivers. African Queen, A River Runs Through It, and one of the best movies ever made which spends most of its time on the river, Apocalypse Now. In the movie, the French woman living on the plantation says to Willard (played by Martin Sheen), “Do you know why you can never step into the same river twice?” Willard answers, “Yeah, 'cause it's always moving.” The best scene, though, is the conversation between Willard, who has come to assassinate the unhinged Colonel Kurtz (played by Brando). They converse about the Ohio river and a gardenia plantation.

What was up with all those movies in the 90s about dead bodies being found along river banks — Short Cuts, Stand By Me, A River’s Edge, and of course, David Lynch’s Twin Peaks? We Gen Xers were so demented.

Supposedly, there are 165 major rivers around the world, but no one really knows the real number. The five longest rivers in the world are the Nile, which starts in Uganda and moves north (odd, right?) to Egypt, the Amazon-Ucayali-Apurimac in South America, the Mississippi-Missouri-Red Rock in the U.S., the Yangtze in China, and the Yenisey-Baikal-Selenga in northern Asia. The Nile is the longest, topping out at 6,650 km. The Danube in Europe flows through 10 countries. The Congo River is the deepest. Rivers serve all sorts of purposes. They provide water, food, habitats, transportation, and recreation, to name just a few purposes. Rivers are really important for food. Fish and other aquatic creatures that live in rivers are consumed. Food is traded on and transported by rivers. Food is grown in or around river banks. Water from rivers irrigates crops.

We wrote a paper on the dynamism and multifaceted nature of rivers as food environments (i.e., the place within food systems where people obtain their food) and their role in securing food security, including improved diets and overall health. In the figure below, we showed the elements of multidimensional riverine food environments.

The paper nicely describes why river ecosystems are so critical. “Rivers can be described as nutrient highways across the earth’s surface, transporting sediment and water, sequestering carbon from the atmosphere, and connecting and storing immense biodiversity through aquatic life. The flow and transportation of sediment create environments for cultivation (e.g. rice farming), with river deltas being one of the world’s most agriculturally productive areas. Rivers support approximately 1/3 of all global food production, and an estimated 70% of freshwater from rivers is used for agriculture.”

There are so many challenges with rivers. The first issue is environmental: climate change, environmental degradation, and pollution are vastly changing these waterscapes - altering their composition and flow. The second issue is overfishing and overallocation, meaning the building of dams for electricity, are altering the riverine ecosystems and marine life and creating water shortages and river connectivity, respectively. As for rivers that cut across multiple countries, who governs these waters and decides who can build dams and where? We see those challenges in large rivers such as the Mekong — where China is building dams upstream impacting many Cambodian and Vietnamese living downstream. We also see this with the Nile, in which Ethiopia is building damns to electrify the nation, which could have massive impacts on irrigation systems for Egyptian agriculture. The third issue is that while rivers transport and contain food, they also bring other things, like diseases and unhealthy foods deep into river communities. This New York Times article discusses how the Amazong brought the COVID-19 pandemic into the far reaches of the Amazon forest.

The spread of covid in just a few months during the pandemic along the Amazon waterways. Source: NYT

“The Amazon River is South America’s essential life source, a glittering superhighway that cuts through the continent. It is the central artery in a vast network of tributaries that sustains some 30 million people across eight countries, moving supplies, people and industry deep into forested regions often untouched by road. But once again, in a painful echo of history, it is also bringing disease.”

The Amazon also carries highly processed foods. According to this article, multinational companies like Nestle had river barges that delivered junk foods to isolated communities in the Amazon basin.

There is also the issue of rivers flooding, damaging infrastructure and harming humans and animals in their way. And now, we are experiencing rivers above us — atomospheric rivers corridors of concentrated water vapor in the atmosphere that wreak havoc. What the hell?!

World WildLife Fund’s solutions for sustainable rivers

I can’t recommend enough the documentary “A River’s Last Chance,” about the Eel River. It delves into the history of how this river has been managed, or lack thereof. The Eel River is in Northern California and has been vulnerable to overfishing of its salmon, logging, floods, droughts, and dams. While the wild salmon population is trying to recover, new cash crops—weed and wine — threaten the salmon once more. It is quite a story of a river struggling to survive.

World Wildlife Fund has a fantastic initiative, Rivers of Food, in which they propose a four-pronged solution towards a more sustainable future for rivers and food security.

Let’s hope rivers can be saved as they provide a vital lifeline for nature, animals, and humans. They are also just so romantic and atmospheric. We used to dwell right near the Tiber when we lived in Rome. It was so magical. The way the early morning light hit the surface of the water, the banks, and the bridges. During the late summer months of the year, the starlings would circle around the Tiber, before settling in for the night in the treetops along the river banks. In Paolo Sorrentino’s La Grande Belleza, the early morning light on the Tiber is captured so beautifully below.

Food Bytes: January 2024 Edition

FOOD BYTES IS A (ALMOST) MONTHLY BLOG POST OF “NIBBLES” ON ALL THINGS CLIMATE, FOOD, NUTRITION SCIENCE, POLICY, AND CULTURE.

Things are off to a great start this new year. New York City finally got a bit of snow after 700 days without the fluffy stuff. It wasn’t much, but it was something. This absence of wintery weather further reinforces the idea that we live in a hotter world for any doubters out there…

It reminds me of a song, we, Sound Furies, wrote several years ago called 6-year snow on our 2nd album 3.3 x 3.3 = S.S.. The lyrics go something like this:

last night it snowed though it's almost summer
it hasn't snowed here for 6 yrs
maybe it was the silence, like a blanket in the night
we don't know why we had this dream

we got up and danced, to the silence of the snow
and then we really woke up at home

Here are some curated and random updates for January’s Food Bytes:

My friend and colleague Glenn Denning, a professor at Columbia University, wrote a fantastic book last year, Universal Food Security, and he is featured in Time magazine on how to feed the world sustainably.

Over the holidays, I read the 2023 Best American Food Writing curated by Mark Bittman, also a professor at Columbia. I loved the story, Is the Future of Food the Future We Want? by Jaya Saxena, written initially for Eater. Speaking of the future of food, is Grubstreet trying to make Steve Ells the found of Chipotle look like a serial killer? Check out what he is up to now…

I am now reading Mark Kurlansky’s The Big Oyster. Who knew how essential oysters were to New York City’s economic growth? If you like oysters, eat up - they are rich in zinc. I have lots of time for Mark’s writing on food history.

Far and Wide published an article on the best thing to eat in every country. There aren’t many surprises. For Italy, they chose Bolognese. Speaking of bivalves, I would have chosen spaghetti alla vongole myself…

This past week had a lot of reporting looking back at 2023 and the impact climate change is having. It was clearly the hottest year and summer particularly on record. Just look at this graph to the right. Not sure anyone needs more convincing but if they do the new Ripple and colleagues paper hits home: “Life on planet Earth is under siege. We are now in an uncharted territory. For several decades, scientists have consistently warned of a future marked by extreme climatic conditions because of escalating global temperatures caused by ongoing human activities that release harmful greenhouse gasses into the atmosphere. Unfortunately, time is up.” YIKES…

About 60 food system experts published the Food Systems Countdown paper and report. I was really proud to get this out in the world. I hope it is now used…Speaking of data, it was great to see Hannah Ritchie of Our World in Data and author of Not the End of the World featured in the NYT. I loved this quote from her:

“The role of science is not to dictate policy. Science identifies the problems. It can identify potential impacts. It doesn’t dictate solutions. The role of science is to say, “If you do this, this is the outcome.” It should not say, “This is what you ought to do.” Even in the book, I try to tread that line quite carefully. I’m trying not to be superprescriptive. We live in democracies. We need to make democratic choices. We move into dangerous areas if we try to undermine democracy in order to tackle these problems.”

Here are a couple of other interesting articles/reports I read over the last two weeks:

  • World Dev paper on forecasting acute malnutrition among children using environmental conditions (precipitation, temperature, vegetation) and lethal and non-lethal conflict activity as predictors. Punchline? These conditions matter.

  • Arid regions are going to get even drier. It's not optimistic for pastoralists and the animals they roam with, who are already significantly constrained. It is estimated that 25% of the world is living with drought.

  • UNEP put out a report, What’s Cooking, that assesses the state and future of alternative proteins. It's a worthy read on the growth and demand of these products.

  • There are so many great articles in the Global Food Security journal. I enjoyed this article by Elizabeth Bryan at IFPRI on gender inequalities and strengthening women's agency to create more climate-resilient and sustainable food systems. Punchline? Women matter. A lot.

  • Systems Change Lab put out a State of the Climate report. It presents a roadmap across the various sectors contributing to and could be a solution in mitigating climate change. They show how far we are off track (see the figure). Punchline? It ain’t pretty. My New Year's resolution is to try to be more positive. This report did not help.

I want to leave you with two videos. The first is the Winterkeeper in the Guardian. This lovely video is about the winter caretaker in Yellowstone National Park who has lived there for 50 years. What a life of a person who has lived tranquility and appreciation in kinship with nature. Oppenheimer seems to be sweeping the movie award season, and it is worth watching the real Oppenheimer to better understand his views later in his life about whether the atomic bomb was necessary. Have a watch.

'Coz I'm the tax man

I get asked a lot about whether taxing soda is effective. There has been a lot published on taxing food and beverages that are deemed bad for us. So what gives? Does taxing soda have any impact on our health? This is my take on the science, but first, let this jig run through your head….

Should five percent appear too small
Be thankful I don't take it all
'Cause I'm the taxman
Yeah, I'm the taxman

I'll tax the street
(If you try to sit, sit) I'll tax your seat
(If you get too cold, cold) I'll tax the heat
(If you take a walk, walk) I'll tax your feet

TAXMAAAAAAAN!!!

Sugar-sweetened beverages (SSBs) are nonalcoholic beverages containing added caloric sweeteners. In addition to carbonated soft drinks or sodas, SSBs include energy and sports drinks, less-than-100-percent fruit or vegetable juices, ready-to-drink teas and coffees, sweetened waters, and milk-based drinks. SSBs are widely consumed worldwide, and the retail sales of these beverages have been increasing over the last decade. Their consumption has been associated with obesity, diabetes, heart disease, and other detrimental non-communicable diseases (NCDs). Because of their unhealthy nature, the World Health Organization has included a range of policy priorities, including SSB taxes, to help countries combat NCDs and improve the overall health of the global population.

Taxes on SSBs have been introduced in 118 countries, with 105 at the national level and 13 at the subnational level, covering 51% of the world’s population. Most SSB taxes are implemented using excise taxes (88%), with a handful of other countries implementing them through mechanisms such as import taxes, differential Value-Added Tax (VAT), Goods and Services Tax (GST), or regional sales tax (see the figure below). These excise taxes occur mainly as tax pass-throughs, in which the price increase of the taxed product falls on the consumer. In the U.S., for example, 70% of SSB taxes are passed onto consumers through higher-priced SSBs.

Types of SSB taxes being implemented around the world

In a systematic review and meta-analysis of 62 empirical studies of SSB taxes across 45 countries, the majority of SSB taxes were implemented as a tax pass-through. While the impacts were heterogeneous across the countries, the demand for SSBs was sensitive to tax-induced price increases, with a mean reduction in sales of SSBs by 15%. The sales resulted in no substitution towards healthier, untaxed beverages (e.g., bottled water). Another review argued that SSB taxes provide no substantive changes to dietary or purchasing behavior due to the lack of substitution towards healthier alternatives. Another study found that while SSB taxes modestly reduced the purchases of some taxed beverages in the taxing jurisdiction, consumers respond to the taxes by increasing cross-border shopping, in which they go outside the taxing jurisdiction and buy those same taxed beverages at a lower cost. However, taxes may spur downstream effects on other industry responses and policies, including reformulating products to reduce sugar consumption in those beverages, as was seen with the graduated sugar tax implemented in the UK.

Of the tax policies around the world, 73% are implemented in low- and middle-income countries (LMICs), with the highest in South Asia. However, LMICs face many challenges in implementing SSB taxes, including a lack of political will and resources, weak national capacity to implement policies, large informal food sectors, and substantial influence of the food and drink industry on policy development.

The question remains whether SSB taxes can result in healthier dietary patterns and reduce the health implications accompanying excess consumption of these products – particularly NCDs. Most of the evidence — particularly from  Nakhimovsky et al., 2016; Niebylski et al., 2015; Teng et al., 2019; and Thow et al., 2014 — suggests that SSB taxes have impacted the purchases of taxed products to varying degrees, but not necessarily long-term and impactful behavior change towards healthier diets and improvements in health. One potential reason may be that the SSB taxes translate to only a 5 to 22-kilocalorie reduction per capita daily. This is insufficient to have a meaningful impact on disease outcomes. Some researchers suggest that one way to deal with this is to raise the current tax rates from the current approximate 5% to 20%. This would also be aligned with the WHO’s recommendation for at least a 20% tax on SSBs. Several countries, such as Qatar and Saudi Arabia, have substantive (50-100%) excise taxes on SSBs, which are more in line with the taxation rates of tobacco.

The question is whether other foods, particularly red meat, should be taxed due to their significant implications on the environment and contributions to climate change. While consuming red meat in high amounts can contribute to NCDs, red meat is also a source of important nutrients. If a tax on red meat makes them prohibitively expensive for those who already struggle to afford these foods, it could put these nutrient-dense foods even further out of reach for the world’s poor. Thus, a “carbon tax” on red meat might be appropriate in wealthy countries with strong social protective measures and in countries with disproportionately high levels of red meat consumption.

Ran my fingers across the world

On the eve of a new year, we are meant to reflect on all that we accomplished (and didn’t) and put forward our hopes and goals for the new year. I find this hard to do as I get older because time seems so warped, and change is hard to measure. When I reflect back to 2023 to see what has changed for me, I am left with blurry memories and vague recollections, much like the three years of living during the pandemic. But there were some bright spots and standout moments.

Our last New Year’s Eve was spent crisscrossing most of Italy, ending in the heel, also known as Puglia (where my family is from), with the idea that we wouldn’t return for a long while. Not that we don’t love Italy, but we spent almost six years living there, and maybe it is time to see other places if we do decide to travel. I had just learned I was granted tenure at Columbia University and would join the new Climate School faculty in July of 2023. Exciting. Now comes the hard part – we had to sell our house and downsize our belongings to snuggly fit into a smaller Columbia-subsidized apartment in NYC. Offloading a house in the middle of a housing crisis with high interest rates is stressful and borderline nightmarish, but we managed to do it. Plus, moving just sucks. No matter how often you do it (and for us, we are at 25 times), it is just a massive hassle. So, the first half of 2023 was one significant stressball transition phase.

Things fell into place once we got to NY in June. We live in the Upper West Side, where I have worked for a long time and where we have lived before, so it all seems routine and familiar. Are we too comfortable and normalized? God forbid that we get too comfortable. It may be time to move to another borough and start another walkabout MaPhattan project. Brooklyn beckons, but the ever-evolving NYC landscape is unpredictable, and it is hard to know where to move that won’t become overly gentrified or where you are not participating in such a predictable path.

On the work front, I published, in collaboration with many stellar scientists, 18 papers, the final one being the Food Systems Countdown Initiative paper and report. I started a new job as a Professor of Climate and Food at Columbia’s Climate School and as the Interim Director of the International Research Institute of Climate and Society. It has been an interesting adjustment since leaving Hopkins, with a lot of my team going on to spread their wings in other institutions. The Food Systems Dashboard is going strong along with other various projects.

On a personal note, we, the Sound Furies, finished our fifth album, Times Edit. My favorite song is Mandelbrot’s Coastline. I traveled a hell of a lot less and will continue on that path in 2024. What I will do in 2024 is spend some time curating and sharing all the photos I have taken on my 60+ country travels. 2023 was filled with ordinary experiences — I got COVID, which sucked. I walked an average of 5.8 miles per day, up from last year, which was 5.2 miles. I tried out the Peleton (there is one in my building) and found it ridiculous but effective. I ate red meat maybe five times and tried my best only to take public transport (maybe got in a taxi/uber 4-5 times) if walking wasn’t an option. I continue to bake sourdough…I decided I like folk music (maybe it’s my age) and succulents (maybe it’s my age). We celebrated our 27th wedding anniversary. I turned 52. We ate in 55 restaurants since arriving in NYC (hey, don’t give me shit, I’m in the food business).

Looking to 2024, the new year brings the opportunity to turn over a new leaf, improve, and make a change. But change is ruthlessly tough, and we are often hard on ourselves when we don’t make those changes “successfully.” And I must admit, I am worried about the changes to come. The poem, What they did yesterday afternoon, by Warsan Shire has been running through my head:

“later that night
i held an atlas in my lap
ran my fingers across the whole world
and whispered
where does it hurt?

it answered
everywhere
everywhere
everywhere.”

Almost half of the world will be voting for new leaders in 2024, and democracy looks pretty fragile to me. I worry about the U.S. elections, as I am sure almost every American does, and the results will impact future decisions about our lives and goals. I am also profoundly concerned about the lack of action on mitigating climate change, what that will mean for everyone, particularly the poorest and most vulnerable, how much they will need to adapt, and with what resources.

But as the late Sam Cooke beautifully sang, a change is gonna come – the question is, are we ready for whatever comes? Because things don’t always change for the better, but they do change. Rebecca Solnit, author of Hope in the Dark, wrote, "Incremental change can happen quietly, and change is rarely straightforward. Victories slip by unheralded while failures are more readily detected.” I will remain hopeful in 2024 as I run my fingers across the world. I am going to remain hopeful. Not because I think everything is going to be okay. But hope for the possibility that the change that is coming pushes us forward to a more sustainable future.  

Food Bytes: November 2023 Edition

FOOD BYTES IS A (ALMOST) MONTHLY BLOG POST OF “NIBBLES” ON ALL THINGS CLIMATE, FOOD, NUTRITION SCIENCE, POLICY, AND CULTURE.

I thought I would write up the November Food Bytes before the onslaught of publications leading up to the COP28 climate meeting takes place. Here is the roundup!

Some interesting articles and books:

The great “godfather of climate science,” Jim Hansen, also a Columbia colleague, has put out a paper with colleagues arguing the planet may be warming faster than previous estimates have indicated by measuring “climate sensitivity” – measuring the earth’s warmth via atmospheric carbon dioxide concentrations. Global CO2 levels hovered around 280 parts per million in the pre-industrial age. Now, they are above 400 ppm. Not everyone agrees with this paper, but no matter, Hansen is sending us clear warnings.

We are more and more worried about how resilient our food systems are in the face of extreme events and shocks, be they climate, environmental, or political. This paper examines the impacts of crop yields related to several agriculture input shocks – nitrogen, phosphorus, and potassium, machinery, pesticide, and fertilizer. Industrialized agriculture systems depend on these inputs, and often, they are imported from other countries. When combined, as you can see in the figure, some areas showed decreased yields for some but not all crops. The yields of barley, maize, potato, and wheat decreased heavily in the western United States. Barley, maize, millet, potato, sorghum, and soybean yields all decreased in northern Argentina, while barley, maize, potato, and wheat. To some extent, sugar beet also saw large yield decreases in Central Europe. Rice yields, in turn, decreased heavily in Thailand, Vietnam, and the southern part of India.

Source: https://www.nature.com/articles/s43016-023-00873-z/figures/3

My friend Bill Dietz, the Director of Sumner M. Redstone Global Center for Prevention and Wellness at George Washington University, and I just published a paper on how the U.S. agri-food sector can contribute to climate change mitigation. The paper is timely for the upcoming COP28 meetings. The U.S. needs to step up!

A new book on the political economy of food system transformation co-edited by Danielle Resnick and Johan Swinnen has been jointly published by IFPRI and Oxford University Press. The summary follows: “The current structure of the global food system is increasingly recognized as unsustainable. While the need to transform food systems is widely accepted, the policy pathways for achieving such a vision often are highly contested, and the enabling conditions for implementation are frequently absent.” Check it out and download it for free here.

Some interesting reports:

Every year, the UN Food and Agriculture Organization, also known as FAO, releases two flagship reports: the SOFI and the SOFA. The SOFA just came out this past week and focuses on the “true cost of food.” That means they assess the hidden environmental, health, and social costs of producing our food. What is their final assessment? Global hidden costs of food amount to 10 trillion dollars, with low-income countries bearing the highest burden of hidden costs. Yikes.

The Global Alliance for the Future of Food released an interesting analysis in this report calling for food systems to wean off fossil fuels. Wouldn’t that be nice….They argue that food production, distribution, processing/packaging, storage, and sales consume about 15% of all fossil fuels generated annually. They argue that the fossil fuel industry holds a lot of sway with governments, making it difficult to “extract” (sorry for the pun) their influence or hold them to account.

A report by the group I-CAN, which looks at the integration of climate and nutrition, came out. It is interesting…nothing new…and much built on the long scientific publications already out there, but I supposed putting it in a layperson report gets the message out there.

Some interesting listens:

Vice did an “expose” on how the Italian mafia has taken over food systems in Italy. Having lived in Italy and interested in Italian deep food traditions, I watched it. The document is not well done, with much speculation and little evidence beyond a few interviews. If it is even true, I wasn’t convinced by this documentary.

John Oliver’s Halloween episode focused on the issues of child labor related to producing chocolate – focusing on Ghana and the Ivory Coast, where roughly 60% of it is produced. A lot of the material is borrowed from Netflix’s Rotten series. Still, the message is clear that many children (1.56 million) are engaged in cocoa production stemming from insufficient wages paid by massive confectionary companies to smallholder farming families working or owning cocoa farms, leaving them in gut wrenching poverty. Such a tragedy. I don’t think John Oliver adds much to the debate – if you want a quick watch, go to the Netflix episode.

In their usual snarky, pick-it-to-pieces style, Mike and Aubrey of the fantastic Maintenance Phase podcast sink their teeth into Ozempic, the weight loss diabetes treatment drug. It's well worth listening to the latest.

Food Bytes: March 2023 Edition

FOOD BYTES IS A (Almost) MONTHLY BLOG POST OF “NIBBLES” ON ALL THINGS CLIMATE, FOOD, NUTRITION SCIENCE, POLICY, AND CULTURE.

So much going on in food and nutrition these days that it is hard to keep up. In looking at what has been published in the last month, three areas dominate ultra-processed foods, climate change, and blue foods. Let’s take each and highlight the latest and the greatest.

Ultra-processed foods: What are ultra-processed foods (UPFs), may you ask? Basically, junk food. But we scientists have to come up with fancy terms and categorize everything. UPFs are a very broad category of foods that generally are made from highly processed, industrialized ingredients not found in the home or in restaurant kitchens. These foods are designed to be hyper-palatable, often conveniently ready-to-eat, shelf-stable, transportable, strongly marketed, and, ultimately, highly profitable. More and more research shows that these foods are detrimental to various health outcomes (obesity, diabetes, cancer, morbidity, mental health, etc.) and could be potentially addictive and environmentally destructive. California, which always leads in food governance (blame it on the hippies), is growing worried about what exactly these foods contain. They are considering banning a number of staple ingredients found in these foods. I cannot even begin to source the sheer amount of literature coming out demonstrating the impact of these devilish foods, but here, here, and here are a few good systematic or meta-reviews. This Wired layperson article is a good summary. If you want to read two people who lead in the science of UPFs, read Carlo Montiero or Kevin Hall. Regardless of all the science coming out, their sales are increasing across almost every region of the world. Why? Well, they are cheap, have a long shelf life, are easily stored and transported for long periods of time, and are damn tasty.

IPCC AR6 Synthesis Report, 2023: Key Summary Figure

Climate and food: Hard too to keep up with everything going on. The most significant update is that the Intergovernmental Panel on Climate Change, also known as the IPCC, has come out with a synthesis report on how much time we have left before the world falls apart. They are surprisingly and cautiously optimistic, arguing that there is still time to address climate change before things start “gettin’ hot in here.” Food is heavily featured in this synthesis report, thanks to our AgMIP friends at Columbia University. They argue that food security and nutrition are and will continue to be significantly impacted, particularly in resource-constrained settings and among smallholder farmers. They also offer a range of mitigation and adaptation strategies, including agriculture, forestry, and other land use (AFOLU) options with reduced deforestation in tropical regions, shifting to sustainable healthy diets, reducing food loss/waste and intensifying sustainable agriculture (they even mention urban ag!).

When I asked Google’s new AI system, Bard, what was the latest science published in “food systems” in the last week, this is what they spit out:

Here are some recent research on food systems:

  • A new study found that the global food system is responsible for about one-third of all greenhouse gas emissions. The study, published in the journal Nature, found that the food system's emissions are mainly caused by the production of meat and dairy products, as well as the transportation of food.

  • A new study found that the global food system is also responsible for about one-third of all water use. The study, published in the journal Nature Water, found that the food system's water use is mainly caused by the irrigation of crops, as well as the production of meat and dairy products.

  • A new study found that the global food system is also responsible for about one-third of all land use. The study, published in the journal Nature Land, found that the food system's land use is mainly caused by the production of crops, as well as the grazing of livestock.

These are just a few of the recent research on the global food system's impacts on the environment. The food system is a major contributor to climate change, water pollution, and land degradation. These impacts are likely to become more severe in the coming years, as the global population continues to grow.

Not too shabby, but a bit outdated (and they don’t provide any citations). Interesting how AI is set to become such a game-changer, and yet, as an expert, asking Bard to do a bit of research, it is pretty generic and lacks scientific nuance, which can be dangerous…Here are some even more recent papers out this week on food systems and climate from a flawed human perspective:

  • Ivanovich and colleagues at Columbia University (see a pattern?) published a paper in Nature showing that if we continue on our current food consumption patterns, this will add 1 °C to an already warm planet by 2100. Most of this warming is driven by what is called high methane foods (methane is another toxic greenhouse gas) like livestock, dairy, and rice (yes, we cannot blame it all on those cute cow creatures). If we made some of the changes mentioned in the IPCC report above, we could cut 55% of that warming.

  • Another paper, again published by Columbia University peeps (they are on a roll), called for more studies to better show how the food security of households and communities is impacted by climate-related shocks. They argue that most studies only examine food production and availability, not access or utilization.

  • And last, and this is self-promotional, a few of us put together an analysis trying to understand if the EAT-Lancet planetary health diet was adequate in nutrients (we didn’t look at environmental impacts or other health impacts, and we are not suggesting to do so). This particular analysis shows that the diet is inadequate in vitamin B12, calcium, iron, and zinc. The EAT-Lancet may not be happy with these results but this is what science is all about — debating on a level playing field, DISproving one’s hypotheses, and not being wed to ideologies. I am not sure right now that everyone at the so-called proverbial table looks at science similarly and instead holds fast to their worldviews, which worries me. But a lot is at “steak.” The EAT-Lancet Commission part has been downloaded over 6,000 times in 4 years. That is pretty insane. So to go against that, dissect it, calls to do it better next time around, or at least look carefully at the data, in which multiple people analyzing the dataset, is, well, what science and the pursuit of truth is all about. But putting one’s arm out to be potentially severed. Bottom line: This paper is about the trade-offs that are par for the course with a grand food systems transformation.

Showing tradeo-offs of policy bundles: Crona et al Nature 2023.

Blue foods: More and more, and this is long overdue, blue foods, aka seafood, aka aquatic foods, are getting more attention. The Blue Foods Assessment highlighted their importance from multiple angles - important contributors to a nutritious diet, some species’ environmental sustainability, their risk of climate threats, and contributors to livelihoods. Some fantastic articles have emerged recently, including a fantastic paper by Christina Hicks and colleagues examining the injustices associated with aquatic food systems. Another paper summarized the BFA around 4 policy objectives to help realize the contributions that blue foods can make to national food systems around the world: ensuring supplies of critical nutrients, providing healthy alternatives to terrestrial meat, reducing dietary environmental footprints, and safeguarding blue food contributions to nutrition, just economies and livelihoods under a changing climate. However, trade-offs always exist, just as above. The figure shows these — the question is, what trade-offs are we willing to live with? And last, on blue foods, the great Roz Naylor at Stanford published a policy landscape paper in Food Policy (thanks, Chris Barrett!) on aquaculture. I had the pleasure of working with her on this. Through a series of case studies, she presents a state-of-play on how aquaculture is playing out globally, and again, where those policy priorities elicit trade-offs that can be detrimental to the environment or nutrition. Check it out.



Diversifying Our Diets, Post COP 15

This is a cross-posted blog from the Berman Institute of Bioethics’s Global Food Policy and Ethics (GFEPP) blog. It was written by Leslie Engel, MPH, a Science Writer Consultant for the GFEPP.

COP 15—shorthand for the fifteenth meeting of the Conference of the Parties to the UN Convention on Biological Diversity—wrapped up in late December with ambitious goals to address the rapid and stunning losses to our natural world. Included within the targets for 2030 is the conservation of 30% of the world’s land, oceans, and waterways; a 50% reduction in food waste, and a “significant” curtailment in overconsumption and waste generation.

The critical role food systems play in meeting these targets was acknowledged during Food Day, a mini-conference within the two-week convening. The day was devoted to discussions on “transforming food systems to address biodiversity loss and achieve food security and nutrition for all by 2030.” As the organizers noted, “food production is the biggest driver of environmental degradation and biodiversity loss: 70% of freshwater withdrawn, 30% of global GHG emissions, 80% of deforestation and the degradation of many other precious habitats such as wetlands and grasslands.”

In the U.S., recent events have underscored how intensive agricultural practices and climate change are interacting to create a troubling feedback loop with dire environmental consequences. A severe drought, coupled with overuse, has reduced the Colorado River to a trickle in places. Americans rely heavily on the river, with one in 10 depending on it for drinking water. The rest of us are making salads with it: 70% of the Colorado River Basin is used for agriculture and over 90% of our winter vegetables are grown in Arizona. 

And we are not the only species relying on it. The river that carved the Grand Canyon also sustains life for a huge variety of unique creatures and ecosystems that will disappear without it. A manager at Glen Canyon Dam described it as a “doomsday scenario” in a recent Washington Post article. 

California’s Central Valley, where 25% of our food is grown, is experiencing similar conditions, the January deluge notwithstanding.

Let’s pause here for a deep breath.

It’s heartening that the international community was able to come to a consensus on protecting the world’s ecosystems. How do we translate the momentum generated in distant conference rooms to our everyday lives?

Here’s one idea: this year, let’s step out of our culinary comfort zones. 

Seventy-five percent of the world's food comes from only 12 plant and five animal species. It’s a startling statistic but think about that salad you ate for lunch. Was it so different from the one you had yesterday, last month or last spring? We can support the environment, our personal health and ultimately, a more sustainable future by diversifying our own palates. 

To jumpstart, here’s a veggie-centered recipe, sans lettuce, the leafy green that science journalist Tamar Haspel once described as a “vehicle to transport refrigerated water from farm to table.” Instead, this colorful and low-waste winter salad features nutrient-rich, cool-weather crops that you may be able to source locally or regionally, including:

  • Radicchio, native to Northeast Italy and currently grown in similar climates within the U.S throughout the winter months.

  • Millet, a highly nutritious and drought-resistant cereal grain that you’ll be hearing more about. The FAO has declared 2023 the International Year of Millets to draw attention to the potential of this small but mighty grain to feed the world in the face of climate change. 

  • Winter squash, a great two-for-one deal since you get the flesh and the seeds as a future snack. Keep the veggie peeler in the drawer; squash skin is edible.

  • Hazelnuts (aka filberts), which are less intensive to grow than other nuts. If possible, use hazelnuts grown in Oregon

  • Citrus, currently in season

Radicchio, Millet and Roasted Winter Squash Salad with Hazelnuts and Orange Vinaigrette
Serves 4 generously/Costs approx. $3 per serving (based on current food prices in a New York City)

  • 1 medium winter squash (about 2 lbs.): delicata, kabocha, buttercup, almost any type will do, except spaghetti.

  • 1 cup millet

  • ½ lb. radicchio (of any variety), torn into bite-sized pieces

  • 2 large navel oranges: use one for zesting and juicing, and the other for the salad.
    I used cara cara oranges here for their lovely pink hue, but any navel-type orange works.

    • 1 tsp orange zest (zest the orange before squeezing it)

    • ¼ cup freshly squeezed orange juice 

  • ½ cup raw hazelnuts

  • Olive oil

  • Optional soft herbs like parsley, mint, tarragon or chives (a great way to use up any herbs you may have lurking in your fridge)

Roast Squash

Arrange racks in the middle and bottom sections of the oven. Preheat oven to 425 degrees.

Cut squash in half and scoop out the seeds (save for roasting!). Slice squash into one-inch pieces, place on a rimmed baking sheet, drizzle with 1 tbsp olive oil and season with salt and pepper. Roast on top rack 25-30 minutes until caramelized and tender. Flip squash halfway through cook time to ensure even roasting.

Prepare Millet
Meanwhile, add millet to a medium saucepan over medium heat. Toast millet 4-5 minutes until slightly golden and fragrant. Carefully pour in 2 cups of water, 1 tbsp. olive oil and ½ tsp. salt. Stir everything and bring to a boil over high heat. Reduce heat to low, cover and simmer until tender, about 15 minutes. Allow to steam for five minutes with the lid on, then fluff with a fork. Spread on a sheet pan or plate to cool. This last step is optional but prevents the grains from sticking together too much. Adapted from thekitchn.

Toast nuts

Place hazelnuts on a rimmed baking sheet. Roast on bottom oven rack for 7-10 minutes, shaking pan once, until nuts are lightly browned and fragrant. Roughly chop nuts once cool enough to touch. If your nuts still have the papery husks attached, don’t worry about removing them. They’re perfectly edible.

Make Dressing

Combine orange juice, zest and ½ tsp salt in a small bowl. Slowly whisk in ¼ cup olive oil. Taste dressing and add more salt and a grind of pepper, if you like. Set aside.

Assemble Salad

Tear radicchio into bite-size pieces. Add to a large bowl and drizzle in half the dressing. Gently massage radicchio leaves with your hands. Add squash and 1 cup millet to the bowl, then gently mix to combine ingredients. Taste the salad and add additional dressing, salt, and pepper if needed.

Slice off the stem and navel ends of the second orange to reveal the flesh and create a stable base for cutting. Using a sharp knife, “shave” off the peel, following the shape of the fruit and preserving as much of the flesh as possible. Then slice the flesh into thin rounds. 

Top salad with citrus rounds, nuts and optional herbs. Buon appetito! 

A note about leftovers: 

  • The salad is best when eaten the day you make it, but radicchio’s crisp leaves are forgiving, so the wilt factor is minimal compared to more delicate salad veggies. Store in the fridge and bring to room temp before eating. 

  • Any remaining dressing can be refrigerated for a day or two. Bring to room temp before using.

  • Leftover millet can be eaten for breakfast like Cream of Wheat or used as a base for grain bowls. It also freezes well for future use. 

 

For more information on the joys of winter vegetables, check out this informative guide from FoodPrint. 

Gas Stoves: More Than a Lifestyle Choice

This is a cross-posted blog from the Berman Institute of Bioethics’s Global Food Policy and Ethics (GFEPP) blog. It was written by Leslie Engel, MPH, a Science Writer Consultant for the GFEPP.

You’ve likely heard the recent flare up regarding gas stoves, inspired by statements from Richard Trumka Jr. of the Consumer Product Safety Commission (CPSC).

This image is a gas stove burner that is turned on with a flame.

@copyright: Scientific American

It turns out that gas stoves are a major source of indoor air pollution from nitrogen dioxide, carbon monoxide and fine particulate matter, which they emit even when not in use. While discussing the health hazards this poses—-childhood asthma, respiratory illnesses, increased risk for cardiovascular disease and potentially dementia later in life—Trumka floated the idea of a ban if they could not be made safer. 

The reactions were swift and dramatic. One chef taped himself to his beloved gas stove in protest, while food activist and chef Alice Waters declared that she’s ready to go electric. On social media, home cooks passionately defended their gas stoves. And then there were the inflammatory comments from elected officials. To cool things off, the Biden administration quickly announced that there were no plans to ban them.

Based on this public discourse, one might think that the only people potentially impacted by gas stove regulations are chefs, aspirational home cooks and politicians. It’s been discussed as yet another lifestyle choice—one of our freedoms—that’s in danger of being taken away from us. 

And right on cue, Senators Cruz and Manchin have introduced the Gas Stove Protection and Freedom Act, which would prohibit the CPSC from using federal funds to enact bans on gas stoves.

“The federal government has no business telling American families how to cook their dinner, which is why Senator Cruz and I introduced bipartisan legislation to ensure Americans decide how to cook in their own homes,” said Manchin in a press release

There’s a lot of hot air blowing around.  

Yet it seems that we haven’t heard from communities disproportionately impacted by the ill effects of indoor air pollution. For example, asthma disproportionately affects low-income families and communities of color: 16% of African American non-Hispanic children, 13% of children of Puerto Rican descent and 11% of kids from homes with incomes less than 100% of the federal poverty level. For comparison, the rate of asthma among white children is 7%.

In a recent study, researchers reported that nearly 13% of childhood asthma cases in the U.S. could be attributed to gas stove usage, on par with secondhand smoke. Those numbers increase in states with higher reliance on gas stoves, like Illinois, New York and California. Kids from low-income households may be at even higher risk of gas exposure due to poor stove ventilation and other factors related to their living situation.  

Many Americans don’t get to decide how to cook their own meals; they live in rental units, public housing or simply cannot afford to replace whatever cooking apparatus they already have. In New York City and Baltimore, gas outages in affordable housing have left residents without a reliable cooking source for weeks and even months at a time. Residents are provided with an electric hot plate, but one has to wonder how this impacts food choices and nutrition in the long run. 

For some, cooking with a gas stove is a lifestyle choice, but for many, it’s simply another structural inequity contributing to poor health outcomes.

By Leslie Engel, MPH, Science Writer Consultant for the Global Food Ethics and Policy Program

Grocery Delivery Services: A Mixed Bag

This is a cross-posted blog from the Berman Institute of Bioethics’s Global Food Policy and Ethics (GFEPP) blog. It was written by Leslie Engel, MPH, a Science Writer Consultant for the GFEPP.

Americans have more ways than ever to shop for the ingredients needed for their meals. This was not always the case. Prior to the first self-service grocery store opening over a century ago, shoppers had to rely on clerks to retrieve and package items for them. Since then—aside from the invention of scanners and self-checkout—the grocery shopping experience has remained largely unchanged. It’s an industry ripe for disruption, and tech companies have seized upon this.

Rowan Freeman, Unsplash License

Enter grocery delivery services. These companies make lofty promises—to eliminate the hassle of grocery shopping, meal planning, preparation, and even the act of cooking itself—while also being good for you and the environment. And more Americans than ever are now using them.

I worked as a recipe manager for a leading grocery delivery startup whose mission is to make healthy eating easy by using artificial intelligence (AI) technology to predict customer food preferences. As a professionally trained chef with a background in public health, I was fascinated with the ability of such services to seamlessly deliver top-quality, nourishing, and sustainable products and recipes to customers, potentially as another avenue to improve health and wellbeing through home cooking. However, as I developed yet another recipe involving ground beef, I began to question how healthy this industry really is, both for ourselves and for our food system.

Convenience, for a price
Convenience, safety, and accessibility are the main appeal of these delivery services. This was especially evident during the COVID-19 pandemic, when many consumers turned to delivery to avoid in-person shopping. In theory, this means that more people will have better access to food, especially those with health, mobility, or other constraints. However, convenience comes at a price, and grocery delivery services pass this cost onto consumers in the form of markups, service, and delivery fees. Additionally, increased food costs due to inflation likely render this convenience financially out of reach for those most in need.

Reduction in greenhouse gas emissions?
There’s some evidence that grocery delivery could be more environmentally friendly than hopping into the car because it reduces greenhouse gas emissions. A study in Washington State demonstrated that it may be more efficient for a fully stocked truck to deliver to multiple households in the same neighborhood rather than individuals driving to the store themselves. But this is a best case scenario. The biggest emissions reductions would require households to cluster their orders together and forgo specific delivery times, thus reducing the convenience factor and the main selling point of such services.

Tim Mossholder, Unsplash License

Reliance on California’s Central Valley
Twenty-five percent of our nation’s food is produced in the Central Valley of California. The area is so integral to business that the company I worked for hired someone specifically from the region to oversee produce sourcing. But its agricultural future is in peril: water is scarcer than ever, severe droughts related to climate change have diminished groundwater stores and decimated crops, and intensive farming practices exacerbate the problem.

Crop failures or shortages were a huge sourcing and supply chain headache with trickle down effects. Customers often complained about receiving an inferior product, or one not as uniform as what they were accustomed to. Receiving a last minute vegetable “swap” presented a whole new set of customer challenges: I don’t like the cauliflower that replaced my broccoli! And how am I supposed to cook this?

The end result was often wasted food, as evidenced in the customer comments I analyzed. Food wasted at the household level is especially egregious because it squanders all the resources that went into growing, processing, packaging, and shipping it. In the U.S., between 73 and 152 metric tons of food is wasted somewhere along the supply chain annually. About half of that waste is happening at the household or food service level. And worldwide, food waste contributes 8% of human-generated greenhouse gas emissions, making it a significant contributor to climate change.

Technology
When customers rated a product or recipe, it became a data point used to further refine the AI, which then “decides” what product or recipe will go into their next delivery. You’ve no doubt seen the effectiveness of this technology in eerily relevant pop-up ads. Similar to how AI learns which ads you are most likely to click on, it can also learn which foods you’re going to enjoy or not. Like that hamburger? You shall receive more ground beef! It becomes a feedback loop designed to retain customers and increase profits, but not necessarily improve your health or the environment.

Looking Ahead
I still believe that grocery delivery services and the technology that drives them are the way of the future and can be a positive force within the food system. AI can potentially be used to improve diets, not just increase profits; researchers have harnessed this technology to help people grappling with obesity and diabetes to eat better.

To improve access for everyone, the U.S. government should make it easier for grocery delivery companies to accept Supplemental Nutrition Assistance Program (SNAP).The USDA is currently piloting a program that enables SNAP recipients to purchase groceries online from select retailers. Incentives should also exist for companies to waive delivery and service fees for SNAP recipients.

In addition, produce should be sourced regionally when possible. Shorter transit distances from farm to fridge mean less greenhouse gas emissions and fresher, more nutritious produce with a longer shelf life that’s less likely to be tossed. Fresh Direct offers a selection of local produce and more services should follow suit. The increased demand could help boost struggling regional agriculture and decrease demand on the imperiled Central Valley. Finally, the biggest thing missing from this new grocery shopping experience are people. AI may be “filling” your cart, but humans still harvest, process, pack and deliver everything we eat for low wages in unsafe working conditions. The pandemic has revealed that the meatpacking industry will go to great lengths–at the expense of humans–to maintain production and profits. Most recently, dozens of children were found to be illegally working as sanitation workers in meatpacking plants. By further alienating ourselves from where our food comes from, we’re less likely to see the value in the people behind the scenes making sure your fridge is full.

Leslie Engel, MPH, is a Science Writer Consultant for the Global Food Ethics and Policy Program.

Understanding human water turnover in times of water scarcity

This writing was originally published in Cell Metabolism in their February issue.

Water covers 70% of the planet; however, only 3% is freshwater, which the global population depends on to drink, irrigate crops, and for our sanitation and hygiene. Water is central to almost all human activity and endeavors and, most importantly, the homeostasis of our bodily functions and health. We know that access to both adequate quantity and quality of water drives optimal health. Still, when in shortage or contaminated, it can cause deleterious effects on various health outcomes, some more known than others (1).

While there is substantial research understanding the health effects of insufficient water intake, there are measurement uncertainties in how much water people consume, retain, and excrete as well as a paucity of evidence on the influence of physical, metabolic, and environmental factors on water homeostasis in the human body. A recent study by Yamada et al. published in Science provides further insight into the determinants of water turnover (WT) or the water processed and used by the body (2). The largest study of its kind, they sampled 5,604 people living across 23 countries across diverse regions of the world ranging from 8 days to 96 years old. They examined whether age, body composition, physical activity, socioeconomic status, and geographical attributes of various regions impacted WT. They did this by having subjects consume 100 ml of water, of which 5% was deuterated. This isotope tracking allowed the investigators to measure WT in a highly accurate and precise way.

Predictably, WT was highest in neonates and decreased with age, positively correlated with free mass, total energy expenditure, and physical activity, and negatively correlated with percent body fat. Interestingly, where people live, and their livelihoods matter for WT as well. WT was higher in those living in hotter and more humid places and higher altitude areas. People with traditional livelihoods, such as hunter-gatherers and subsistence farmers, had higher WT than those working outside agriculture. Furthermore, people living in countries characterized as having a low human development index (HDI)—a comprehensive composite index that measures the different dimensions of human development, including standards of living, life expectancy, and education—had higher WT than those living in countries with middle- and high HDI, even after adjusting for physiological and environmental factors.

While some of these results may not be surprising regarding age and biology, they present clear warning signs of vulnerability when considering looming global scenarios, trends, and shocks to water security, with poor populations disproportionately suffering the most severe consequences (3). The world is already grappling with water scarcity—the availability of water depends on an intimate dance between a region's water demand and water supply. As it stands, 4 billion people live with severe water scarcity at least one month a year, with nearly half of those people living in China and India. Half a billion live with severe water scarcity all year round (4). Distressing still, 784 million people worldwide lack access to safe drinking water (5). The figure below shows how these numbers break down by the four major country income groups, and climate change will likely worsen this situation.

Figure 1: Number of people (millions) without access to safe drinking water, 2020

Legend: Each bar represents the surface (drinking water directly from a river, dam, lake, pond, stream, canal, or irrigation canal), limited (drinking water from an improved source for which collection time exceeds 30 minutes for a roundtrip including queuing) and unimproved (drinking water from an unprotected dug well or unprotected spring) sources of drinking water by country income classification. Source: World Health Organization and UNICEF Joint Monitoring Programme, 2021

Climate change will have significant impacts on how much water is available as well as its quality. Already, water systems that provide freshwater to human populations are drying up and polluted from overuse and runoff, much of this coming from agriculture and other anthropogenic forces (6). Water ecosystems around the world will also continue to be strained and stressed. For example, since 1900, approximately 68% of wetlands have been lost, which are essential ecosystems that purify drinking water systems, among many other functions (7). In addition, extreme weather events related to climate change, such as changes to precipitation and severe drought, as well as the melting of glacier ice, is and will continue to impact water resources. There will also be a decline in the quality of water sources due to anthropogenic and natural factors, along with an increased demand for water due to higher temperatures and evaporation rates. As a result, water insecurity under "business as usual" climate scenarios will worsen (8).

Human demand for water worldwide has increased six-fold over the past century and continues to rise at around 1% per year due to the growing population and global economy (9). At the current consumption rate, by 2025, two-thirds of the world's population may face water shortages (10). What will be the consequences for those vulnerable populations living in countries of low HDI given their increased demand for water? Even a slight imbalance in the delicate homeostasis of WT could put these populations at disproportionate risk for various health disparities, along with constraints on access to improved water safety and quality.

We are just beginning to understand the importance of how water is cycled through the body and how to measure it. Yamada and colleagues shed further light on the factors influencing how water is used and excreted in the body. One gap they highlight is the inability to measure the influence of water coming from food on WT. For those who work in food security, it will be necessary to understand how the quality and diversity of diets contribute to and potentially further protect water homeostasis in distinct biological, sociodemographic, and geographical contexts. Understanding this relationship could spur joint policy action among communities concerned with food and water security. With climate disruption continuing to threaten the quantity and quality of food and water sources, scientific and geopolitical collaboration has never been more urgent.  

References

1.     Popkin, B.M., D’Anci, K.E., and Rosenberg, I.H. (2010). Water, hydration, and health. Nutr. Rev. 68, 439–458.

2.     Yamada, Y., Zhang, X., Henderson, M.E.T., Sagayama, H., Pontzer, H., Watanabe, D., Yoshida, T., Kimura, M., Ainslie, P.N., Andersen, L.F., et al. (2022). Variation in human water turnover associated with environmental and lifestyle factors. Science 378, 909–915.

3.     Dell’Angelo, J., Rulli, M.C., and D’Odorico, P. (2018). The global water grabbing syndrome. Ecol. Econ. 143, 276–285.

4.     Mekonnen, M.M., and Hoekstra, A.Y. (2016). Four billion people facing severe water scarcity. Sci. Adv. 2, e1500323.

5.     World Health Organization and UNICEF (2021). World Health Organization and UNICEF Joint Monitoring Programme. https://washdata.org/data/household#!/dashboard/new.

6.     van Vliet, M.T.H., Flörke, M., and Wada, Y. (2017). Quality matters for water scarcity. Nat. Geosci. 10, 800–802.

7.     Davidson, N.C. (2014). How much wetland has the world lost? Long-term and recent trends in global wetland area. Mar. Freshw. Res. 65, 934.

8.     IPCC (2022). Climate Change 2022: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change (Cambridge University Press).

9.     Water, U.A.U.N. (2020). United Nations World Water Development Report 2020: water and climate change (United Nations Educational, Scientific and Cultural Organization).

10.   World Wildlife Fund. (2023). Water Scarcity https://www.worldwildlife.org/threats/water-scarcity#:~:text=Billions%20of%20People%20Lack%20Water&text=By%202025%2C%20two%2Dthirds%20of%20the%20world's%20population%20may%20be,and%20economic%20decline%20may%20occur.