A climate analogue is a compendium of plants from all over the globe that adhere to similar climatic qualities and global positions. For Jeddah, similar locations were found in Mexico, Namibia, Mauritania, and India. Thus the following plants are either known to grow in the region, or are likely to grow there, based on similarities in latitute, elevation, soil profile, precipitation, and other factors. There may be other useful plants that would fit in a niche within a food forest or a managed grazeland which I have missed. This does not include plants I would put in a perennial vegetable garden at the moment–in other words these do not include all the zone 1 plants I would use, which would make for a different, more intense, and less drought-tolerant guild. Some plants show up under more than one category.
One of the series I plan to write for the blog is a plants overview–pick one of the species I’m growing and go into detail on it. When I get that started, these will be the first plants I cover, though I may add to or subtract from the guild as experience dictates!
- Chloris gayana Kunth
- Distichlis spicata
- Pennisetum divisum
- lasiurus sindicus
- stipagrostis drarii
- Smilo Grass oryzopsis miliacea
- Harding grass phalaris tuberosa
- Canary Grass phalaris arundinacea
- Hairy Beard Grass andropogon hirtus
- Erhart’s Grass Erharta calycina
- Tall Fescue festuca arundinacea
- Broad Fescue Festuca elatior
- Tall Wheat Grass Agropyrum elongatum
- Mongongo: Schinziophyton rautanenii
- Date Palm Phoenix dactylifera
- Olive Olea europaea
- Pomegranate Punica granatum–Roman
- Fig Ficus carica
- Guava Psidium
- Mulberry Morus
- Citrus glauca
- Citrus medica
- Jujube Ziziphus ziziphus & spinacristi
- Carob Ceratonia siliqua
- Tamarind Tamarindus indica
- Drumstick Tree Moringa oleifera & Moringa Peregrina
- Mango Mangifera indica
- Loquat Eriobotrya japonica
- Pitaya Hylocereus undatus
- Columar Cacti Cereus peruvianus
- bitter melon: momordica charantia
- Passion fruit: passiflora edulis
- Grape: Vitis vinifera
- luffa gourd: luffa aegyptica
(excellent for coppicing, pollarding, firewood, timber, forage, mulch, and nitrogen fixing. I have marked those that are known to perform hydraulic redistribution as HR)
- prosopis juliflora (HR)
- Prosopis Cineraria (HR)
- Leucaena leucocephala
- Sesbania Sesban
- Parkensonia aculeata
- Albizia Lebek
- Casuarina spp (Note as of 2014–all but 3 of the initial 30 casuarinas we planted have died)
- Acacia seyal
- Acacia Senegal
- Acacia Tortilis (HR)
- Ginger Zingiber officinale
- Turmeric Curcuma longa
- Cardamom Elettaria Cardamomum Maton
- hibiscus spp
- Coastal Pigface Carpobrotus virescens
- Baby sun rose Aptenia cordifolia
- Bay Biscayne creeping-oxeye Sphagneticola trilobata
- Lippia Phyla canescen
- Rosemary Rosmarinus officinalis
- Sage Salvia
- Thyme Thymus vulgaris
- Sweet Marjoram Origanum majorana
- Oregano Origanum vulgare
- Felty Germander Teucrium polium
- Jamaica: hibiscus sabdarrifa
- Tagart Bush: Maerua crassifolia
- Horseradish tree Moringa peregrina
- Sanamaki (senna): cassia senna L. (perennial herbaceous in sandy soil)
- Henna lawsonia intermis (perennial fragrant shrub)
- Miswak salvadora persica (tree)
- Neem Azadirachta indica (tree)
Cash Crops (trees):
- Mongongo–staple nut tree/oil tree
- Frankincense: boswellia sacra, boswellia seratta
- Myrrh: commiphora myhrra, balsamodendron myrrha
- Gum Arabic (?): acacia seyal, acacia senegal
- Moringa: oil, compost tea, seeds
In the last post, I wrote about how if the major cycles for weather in the middle East were holding true, the Arabian Peninsula would be receiving more rain than it has in the recent past, while the opposite is actually true. This post will explore the first major edge where development needs to take place to start greening the Arabian Desert, and explain my hypothesis for why rain isn’t coming, and how desertification is a self-perpetuating loop of death.
I live in Jeddah, which lies on the Tihama plain–a narrow strip of land between the red sea and the mountains of the hijaz, which run about 45-60 kilometers off the west coast of the Arabian Peninsula. Humidity on this plain is very high because of evaporation from the red sea. This can frequently be seen live thanks to the University of Madison-Wisconsin’s global composite water vapor map. While the Arabian Peninsula is often black (very dry) there is frequently a band of grey along the hijaz and in Yemen & Oman. Below is a picture of what the moisture looks like at the time of this writing:
Available moisture in the atmosphere on 21 September, 2014
Some of this moisture is coming off of the ITCZ (you can see the white band of clouds moving across Africa and the Indian Ocean), and some of it is coming off the Red Sea. On the tihama plain, where I am, we should frequently be experiencing an orographic lift, wherein the moisture is driven up into the atmosphere by the mountains, causing clouds to form and rain to fall. I have witnessed this in Al Baydha, which is located about 45 KM south of Makkah, and West of Taif. When it rains in Al Baydha (which it has twice, since 2010), the clouds do not come from the sea in the west, but from the mountains to our east. The clouds form east of us and then are pushed west, causing rain to fall in our area.
Orographic lift caused by mountains is the primary driver of rain in the hijaz: from the Encyclopedia Brittanica
So if there is moisture in the air, and if that moisture is experiencing orographic lift, then why isn’t it raining more often?
The fact is, there are 3 factors inhibiting greater rainfall on in the hijaz that we need to tackle if we’re going to green Arabia.
2: Surface Temperatures & the Dewpoint
3: Availability of Nuclei for Raindrops to Form
“When desert dust reaches heights above 5 km, it absorbs and reflects back to space some of the solar radiation, and so warms the mid-troposphere (Kishcha and others 2003) at the expense of cooling the lowest levels. This generates a downward airflow that exacerbates desert conditions. The added dryness can lead to more desert dust, thus amplifying the initial effect. Desert dust particles can impair precipitation from potential rain clouds, and keep the desert drier, dustier and even less favourable to precipitation in a reinforcing feedback loop, which further increases dust generation by deserts and the likelihood of its transport to non-deserts. Far away from deserts, the transported dust may suppress precipitation from convective clouds by inhibiting the formation of raindrops (Rosenfeld and others 2001)” –Cited from the United Nations Global Deserts Outlook”
A huge dust storms swings through the empty quarter from the Arab Gulf. Source: earthobservatory.nasa.gov
I’m going to connect these dots a little more: When large sand particles strike bare ground, they release tiny pieces of dust (20 microns or less) into the high atmosphere, which inhibit raincloud formation, warm the part of the atmosphere where clouds would form, and increase downward wind, thus increasing the amount of sand that strikes the desert ground, and releasing more tiny pieces of dust. Thus we have a feedback loop that increases with intensity as desertification progresses, making it harder and harder for precipitation to occur, which in turn makes it harder for plants to live, and thus exposing more bare ground to the buffetings of the winds and dust. As bare ground increases, the land becomes less and less able to absorb and retain moisture, thus increasing the rate of evaporation. In short, dust is enough by itself to kill the rainfall and the land’s fertility, and once the cycle of desertification is underway, it will grow on itself until everything is dead. (More scientific information on this cycle can be found here.)
This process, specifically in the Arabian Peninsula, has been observed and recorded by Craig Dremman, rather convincingly in his post here. The picture below is a teaser:
Super Category 5 Typhoon Vs. Giant Arabian Dust Cloud in 2007. Click the link above to see who won in this meteorological death match between an unstoppable force and an immovable object!
SURFACE TEMPERATURE AND DEWPOINT
The dew point is the temperature at which water in the air condenses at the same rate at which it evaporates. If the temperature of the air falls below the dew point, you could precipitation (assuming pressure stays the same) while if the temperature stays above the dew point, you could no precipitation. When bare soil (one of the fundamental descriptions of a desert) is exposed to sun the temperature rises, creates convection, and makes it very difficult for the temperature to fall below the dew point.
Dew condenses on a spiderweb because the temperature has fallen below the dewpoint. Source: http://www.stuffintheair.com/Definition-Dew-Point.html
This is compounded by the lack of water in the soil. NASA’s Earth Observatory has a page on the physical processes that cause drought that talks about wet soils vs. dry soils and the impact they have on drought. When soils are wet, the evaporation from bare soil can help create clouds, whereas when soils are dry, there is no evaporation taking place and thus no cooling effect.
Availability of Raindrop Nuclei
For water to move from a gas to a liquid, it needs something to condense on. If you ever have a couple of cold beverages outside on a humid day, the water collecting on the outside of the can or bottle is being pulled out of the air and condensing on your drink. The same process is required for clouds to form–water in the atmosphere condenses on tiny (1/100th the size of a raindrop) particles. This is initially why scientists used to think that dust in the atmosphere contributed to cloud formation (though they were wrong) because they thought the dust could act as a condensing nucleus. This fact is the basis for the idea behind cloudseeding.
Here is the tricky thing: Not all cloud condensing nuclei are equal. Kenya’s tea plantation area of Kericho has the highest number of hailstorms per year on the planet. After some studies done to try to figure out the cause of all these ice storms, it was concluded that the tea trees themselves were the source of the hail storms. The tea litter would be stirred up by workers picking tea leaves, and waft up into the atmosphere. Here is the kicker: the ice nuclei was able to form around tea litter at a temperature 5 degrees warmer than litter from the surrounding forest. The atmosphere could be warmer and the ice would still form as long as the nuclei for that ice was tea litter. Do you see those italics? This is crucial! Ice forms around tea litter nuclei between -3C and -5C. Silver iodide, the material used in cloud seeding to create rain, requires temperatures of -9 to -10C. The point is, rain will form around organic materials created by some trees more easily than around the best material used by geoengineering companies whose job it is to create rain through cloud seeding.
There is one more gaping lack of raindrop nuclei to be mentioned here: that created by volatile organic compounds emitted from trees. A study from 2008 in the Amazon watershed noted that “the forests emit a large amount of volatile organic compounds (VOCs) which contribute to produce shallow and relatively warm clouds, very efficient to induce rains in the region.” Aside from organic litter, the VOC’s created by the respiration of a forest efficiently lead to cloud formation and rainfall. In a desert, where there are no trees, almost no organic material at all, and since dust is a major inhibitor of cloud formation, the climate must depend on nuclei being brought in from other places–carried by advection or wind.
A photo from Al Baydha, where I work. Where is the ice nuclei supposed to come from?
So there you have it. If the weather in the Arabian Peninsula were following the typical pattern of increasing rainfall as the ITCZ moves North, rain would be increasing. Instead rain is decreasing, and there are 3 principle obstacles to overcome before that can change: dust, temperature, and the lack of rain nuclei. These three factors feed on each other–leading to decreased precipitation, a decrease in the soil’s ability to retain water, less plant life, more bare soil, more dust, higher temperatures, less nuclei, going on and on and on until the land is dead and incapable of supporting life except for those that are the most specialized and extreme. This cycle must be stopped.
At this point, if you are following all of my posts in this series (which you should!) you have a basic understanding of the natural cycles of rainfall in the Arabian Peninsula as well of the destructive cycle of desertification. After the next few posts, the solutions–the things that we as people can do to reverse desertification and restore productivity to these denuded lands should become obvious. If we understand the problem well enough–so well that we comprehend its context and its causes and its effects–the solutions will present themselves.
The patterns and cycles of nature are the dominant context for any climate, and if we want to move from one type of climate (sweltering desert with less than 70 mm rain per year, no carbon in the soil, no organic matter in the soil, evaporation rates exceeding 3000 mm per year, and other foreboding characteristics) to another (productive Savannah yay!) we have to understand both point A and how the major cycles brought you there, and point B–how to work within those cycles to create a different climate.
This post is about understanding point A of where the Arabian Peninsula is (or where it should be) and getting some crucial details of the major cycles determining it climate.
The ITCZ’s path in 2014, in January (blue) and July (red).
The first cycle we need to know about in the Arabian Gulf is the Inter Tropical Convergence Zone (ITCZ). This is a band of clouds caused by tropical convergences that shifts North and South of the equator (North in the summer and South in the winter from the Northen Hemisphere’s perspective), and due to an unknown number of factors, shifts north or south. In the Indian Ocean, the ITCZ is strongly correlated with summer monsoons. Historically, as the ITCZ has moved North, the monsoons have moved further North, bringing heavy rainfall into Oman and the middle of the gulf. For instance, one particular study that monitored Changing Moisture Sources Over the Last 330,000 Years in Northern Oman found that almost all groundwater recharge in Northern Oman occured at times when the ITCZ shifted north. In other words, when the ITCZ goes north, it pulls rain and monsoons along with it, enough that it is responsible for almost all groundwater in the northern area of Oman. A recent Master’s Thesis from KAUST found that this is actually true for the whole Arabian Peninsula up to a certain latitude–precipitation and the ITCZ follow each other up to a limit of 22 degrees North (which corresponds with Northern Jeddah!)
In short, as the ITCZ shifts North, summertime rainfall in the Arabian Peninsula up to at least 20 degrees latitude North, and potentially as far North as Jeddah.
In that respect, there is good news! The ITCZ has been moving north since the mid 1970s (a recorded .5 degrees North and continuing) which, according to initial studies is increasing cloudiness in Southern Arabia and the Sahel region of Africa, and prompting higher temperatures in Northern Arabia (unfortunateley there are no specifics on what the authors consider Northern Arabia–speculation is it could be as far north as Syria, which could be part of the explanation for one of the longest droughts they’ve had in the Syrian northeast). An increase in cloudiness would typically be associated with an increase in rainfall, but unfortunately, that is not the case in present day Arabia. Despite the ITCZ moving north, rain has actually decreased!
A monsoon hits the coast of Oman in 2010. Andyinoman.com
At my work in Al Baydha, which is in the Makkah province of Saudi Arabia, I have had the chance to ask many people about the weather, some of whom are over 80 years old. The old folks in Al Baydha have told me that it used to rain three times a year. These are unlearned people who do not know their own birthdays, but they remember a time when there was a summer rain and two winter rains, and they would feed their animals from trees during the summer by hitting tree trunks with sticks and causing the leaves to fall. In the winter time their animals would eat grass. Other people in Jeddah have informed me that “it has not rained the way it used to in 50 years”. These are anecdotes, but are corroborated by many many witnesses who aren’t just remembering the good old days; they are also struggling with massive shifts in their lives because they can no longer support their animals on their land, due to a lack of rainfall!
How can this be? If the ITCZ has been trending northward since the at least the 1970’s, why is rainfall dropping?
That is the subject of the next post, wherein I will discuss more regional and localized cycles of weather that are fighting (and winning!) against the increased moisture brought on by the ITCZ’s northward trend.
The above graphic is a map of rivers that once existed on the arabian peninsula, in a time when it was populated by crocodiles, hippos, elephants, and a lush array of foliage to support such an ecosystem. Most recently the peninsula had this type of climate between 10,000 and 6000-5500 BCE. scientists have also identified lakes that existed in the current Empty Quarter. The timing for 6000-5500 BCE is curious, because it corresponds with the time that agriculture was showing up, but I’ll get into that later. Aside from the wetter periods in prehistoric times, it’s likely that rivers existed much more recently than 7000 years ago. Here are two maps from the 1570’s, one by Ruscelli Ptolemy, depicting rivers flowing through Yemen, East into the Arabian Gulf, as well as into the Hijaz (Source is Leen Helmlink’s site). And while the maps would not be considered accurate by today’s standards, just the reports that rivers were here that recently is intriguing.
A 1570s map from Ptolemy with rivers crisscrossing Arabia.
For a moment I would like to go back to the first map, though:
Source: “The Prehistory of The Arabian Peninsula: Deserts, Dispersals, and Demography” by Growcutt & Petraglia. Evolutionary Anthropology 21:113–125 (2012)
Do you notice the pattern here? Almost all the rivers have their sources in the mountains, with most of them sourced in the hijaz and the Hajar Mountains. There are some that flowed out of the Empty Quarter, which would have found their source in lakes, but all the rest stem from the mountains. Notice the enormous alluvial fan (somewhat like a delta) entering the sea in modern-day Kuwait. This was an enormous amount of water!
There are two points I am trying to make here:
- Just because a place is a desert now does not mean that it has always been a desert, nor does it mean that it will stay one permanently.
- Any work seeking to restore rivers in a desert must focus work first of all in the mountains, because of their impact on rainfall and because they are the high point of any watershed.
In the next post I will discuss the major weather cycles that have affected the dry/wet cycles in the penninsula, as well as why currently, if the patterns held true, Arabia should be getting more rain now than it actually is.
This subject is going to take up a large chunk of the blog, yet I am the least experienced and the least knowledgable on this subject compared to the other two. I’m not a farmer, a botanist, an ecologist, a geologist, a meteorologist, a soilologist, or a politicologist. I just really love food, and I love America. I even love American food. And there’s no question that our food systems need to change–both for our health and our security.
I grappled a lot with what to call this theme–wrestling between the words restoring, reviving, revolutionizing, healing, and transforming America’s agriculture. It may seem a bit arrogant to you for a non-expert such as myself to call for a transformation in our food system, but doing that would be no less herculean than working on converting the Arabian Peninsula into productive land, which I’m already working on. Besides, this is what I’m passionate about and everyone starts somewhere.
I’m going to use this space to become an expert on how all those ologies influence our food system. I’m going to read and study our food system, and then all that learning is going to be condensed here so that you don’t have to do all the sorting. I also plan to interview experts and post those here (which may even expand into a podcast).
Over the next few years, this is what I plan to explore regarding America and its food, though I reserve the right to not go in the order I’m setting out here, and to add or subtract topics. If you follow along, then at the end you’ll be an expert too!
1: Setting the Stage
- The Anthropocene: Hunters/Gatherers vs. Farmers Vs. Gardeners
- The Oil Age
- Post WWII & The Pax Americana (Yes this has to do with food. Come back later to find out why!)
- The American farm in 2014
2: The Problems with Industrial Agriculture
- Erosion & Topsoil Loss
- Cides: pesti, fungi, and herbi
- Fertilisers & Other Oil Byproducts
- Soil Health & Soil Carbon
- GMO’s: The Ugly, the Bad, and the Potentially Good
- CAFO’s, superbugs, and delicious meat
- Water and the American West
- Why arguments of Organic vs. Conventional are lame and entirely missing the point
- Why “sustainable agriculture” isn’t
3: Policies Create Incentives; Incentives Drive Behavior
- Getting to the bottom of the Food Bill
- The rise of the large farm, and Big Agriculture
- Politics, Policies, Politicians, and Power
4: An Opportunity for Innovative Disruption; Transforming America’s Agriculture
- The Ecological Agriculture Umbrella: Regrarianism, Restoration Ag, Permaculture, Holistic Management, etc.
- The Profitable Farm
- The Problem is The Solution: Leveraging Big Companies To Change the Incentives
If you love to eat, or if you would like your offspring to eat in the future, stick around, sign up for updates, and we will become experts together and work on transforming America’s agriculture.