Category: Dust, Climate, Environment, and Society

Some 100 miles east of San Diego, lives a big agri-town called Imperial Valley (IV) that supplies 2/3 of the winter vegetables and 1/3 of the fruits/vegetables consumed in the entire US. Majority of IV residents are hispanic with 25% living below poverty line and the majority of farmworkers are migrant workers coming from Mexicali across the US-Mexico border. IV has high rates of asthma (one in five children) and the highest heat-related illness rate in the entire state. Several environmental threats contribute to these issues, including the harsh desert climate, the shrinking Salton Sea, blowing dust storms, pesticides-laden runoff from highly irrigated lands, agricultural activities that produce dust and smoke, rapid urbanization, industrial expansion, and now the lithium exploration activities.

State and Federal government representatives, local NGOs and community members, researchers, and most importantly, the farmworkers, met to discuss about how to deal with the emerging environmental challenges of the region in an event called EJSummit. The Environmental Health Leadership Summit (EJSummit) is an annual event organized by a local community organization called Comite Civico del Valle now in its 13th year. The event occured on October 22/23 this year, right next to the agricultural fields of the IV in El Centro, CA.

Following points were noted:

The hot brine below the Salton Sea (not the Salton Sea water) has enough Lithium to meet 1/3 of today’s global demand. The proposed Direct Lithium Extraction method extracts lithium from brine directly using more environmental friendly technique using a adsorption material thereby rejecting the brine which is reinjected underground, but the technology has not been implemented in industrial scale so the reality of anticipated ‘Lithium Valley’ is yet to be realized.
The Salton Sea continues to shrink due to high rate of evaporation combined with reduced inflow of water caused by the Quantification Settlement Agreement (QSA) of 2003 that diverted some 15% water to San Diego region. The local people mentioned that many people have lost their jobs due to reduced agricultural activities, caused by the reduced water inflow to the IV crop fields.
Speakers included 84-year old living legend Preston Arrow-Weed (in picture), a member of Kumeyaay tribe, who lived in this region for thousands of years. Who else can better teach how to reduce our environmental footprint and to live in harmony with nature?

Summer is approaching its peak, are you prepared?

By Sagar Parajuli

On June 25, 2024

In Dust, Climate, Environment, and Society

I almost dozed off on a red light yesterday. What could be the reason?

*Myself during the installation of heat stress sensors (black globe thermometer, temperature/humidity sensors, and pyranometer) in Imperial Valley, CA in May, 2024.*

I don’t turn on my A/C to save cost, energy, or environment whatever one might think of, unless it is unbearably hot. I only turn on the fan. Yesterday was not an extreme day anyway. Just a normal weather day in the upper 70s. And my car is always parked indoor whether at home or office. And I had enough rest for sure. So what else could be the reason?

May be CO? We know that exposure to carbon monoxide can make us sick and even unconscious depending upon the concentration. Where else can be its greatest risk, other than in a car?

May be Oxygen? We know that low oxygen level can also make us sick. Again, where else can it be lower than in an enclosed box? Oh sorry, I forgot about the high mountains.

May be heat? We all know this is also a possibility. We see more people dozing off in summer everywhere, even in meetings and conferences. :).

May be many of you have also experienced something similar. If it happens during a 15-minute drive, imagine what those long haul drivers have to go through, who have no choice but to drive for more than 12 hours everyday. I am 100% sure, coffee can’t solve this problem, however big your cup may be. This is especially critical in summer.

It could be any or all of the above factors. But summer heat is probably the most likely factor here.

With the above context, the question I would like to ask today is why the heat-related deaths are much higher in the developed countries than in developing regions such as Africa or India? As far as I know, the most intense heatwave in the recent history in India occured in 2015 and only about 2500 people died when the maximum temperature rose close to 50 degree celsius. In contrast, more than 60,000 people died during the heatwaves of 2022 in Europe when the maximum temperature rose to something similar.

Humidity has a role to play on heat stress, and the data from India may not be accurate for various reasons, but these factors can’t explain such an order of magnitude discrepancy.

What could be the main reason?

The answer has to lie in our modern way of life. We are spending most of our times indoor which is interfering with our body’s ability to acclimatize. We, the city dwellers, have become a new species that can only survive within a very narrow range of temperature T±ΔT.

The term acclimatization probably needs to be redefined. Traditionally, it referred to how people adapt to different climate regions based on geography. But now, because of our HVAC way of life, the exposure to high temperature is more based on indoor vs. outdoor temperatures than the temperature in region1 vs. region2.

The way we define heatwaves also needs to be reassessed. Normally, it is defined based on how far is the daily maximum temperature from the historical average value in a given location. But, with our indoor way of life, the average base temperature needs to represent our ‘indoor’ temperature where we spend or live most of our time. Obviously, it is going to be different for different people. It might even be associated with social structure and poverty level—just my naive guess.

It is not only about heat, it is also about oxygen level. Although oxygen is the most vital element of life, it’s study has received the least attention for some unknown reasons. One such eccentric study (I wonder how they received the funding) in a Journal of American Chemical Society, the oxygen level is declining in large cities globally, and that the increase in heatwave occurrence was correlated with reduced oxygen level.

Increasing number of studies are showing that air pollution, oxygen level, extreme weather events, occurrence of heatwaves, energy demand all of these are correlated. Our environmental problems have become much more complex nowadays. We need to rise above our traditional area of expertise and think differently if we want to solve these problems. We have to put all these pieces of the puzzle together to know whether the puzzle is a tiger or an elephant.

Together we can.

Cloud seeding and weather modification

By Sagar Parajuli

On January 25, 2023

In Dust, Climate, Environment, and Society

Imagine a world without rainfall. We call it droughts. Or imagine a situation of torrential rainfall and flooding, like in Pakistan last year.

And imagine a world where all our groundwater reserves have dried up. This is not too hypothetical a scenario — the world’s groundwater reserves are already declining. Groundwater is no different from fossil fuels – it is going to deplete one day if we continue to extract without allowing it to recharge.

A drought does not kill in hundreds – when it happens, it kills millions. China, India, Bangladesh, Africa, and even Russia and USA have faced such droughts in their history. And flooding has similar consequences – it causes extensive loss of lives and properties.

So what can we do to prepare ourselves for such adverse scenarios or natural calamities? How can we make sure that we have enough freshwater resources to meet the demand of an ever-increasing population which is already 7 billion?

Cloud seeding is one potential solution. Cloud seeding can be used both to suppress or enhance rainfall. If used appropriately, the application of cloud seeding technology has many possibilities — from enhancing rainfall, snow packs, and groundwater reserves — to suppressing hails, the great enemy of farmers, which can destroy large crop fields in minutes. Cloud seeding is relatively a mature technology used since the 1950s when scientists first discovered the seeding ability of dry ice and silver iodide. It was extensively applied in the late 20th century but it slowly lost momentum afterward for various reasons. Its exploration is again gaining attention as we face prolonged droughts, heatwaves, flooding, and fires worldwide.

This week, scientists and policymakers from around the world working in the field of cloud seeding and rain enhancement are meeting in Abu Dhabi to discuss these and other related issues aiming to find water solutions for the future.

On the first day of #IREF organized by The UAE Research Program for Rain Enhancement Science (UAEREP), we saw several interesting new approaches in cloud seeding works, from the use of electrical charge to acoustic methods for rain enhancement. Today was another engaging day discussing the process-level understanding of aerosol-cloud interactions and the adoption of cloud seeding technology by countries such as Ethiopia and Thailand for tackling their water problems. For anyone interested in understanding rain enhancement technologies, below is the link to today’s program.

Extreme heat and air pollution kill!

Category: Dust, Climate, Environment, and Society

Imperial Valley Environmental Justice Summit

Summer is approaching its peak, are you prepared?