📹 Ocean Productivity – Seasonal Cycle Tropical Zones
Here we explore the seasonal cycle of phytoplankton and zooplankton productivity in tropical latitudes, which typically experience …
What is causing the productivity slowdown?
The study reveals that economic growth has slowed down due to a decline in capital deepening, a slowdown in investment, a lower growth of allocative efficiency, mismeasurement of aggregate productivity, and a slowdown in global trade. The authors identified cyclical factors such as the financial crisis of the later 2000s and longer-term factors such as the shift to more intangible forms of capital.
The study also found that the rates for new firms entering and exiting the market have declined, and pure profits and concentration have increased, causing concerns about productivity growth from improved resource allocation.
The study also highlighted the impact of innovation on long-term growth, highlighting that the private sector’s investment in research and development may undermine the positive impact on productivity. However, the researchers caution that it would take time to see the effect of new technologies and innovations on productivity.
Why is productivity low?
Low productivity is primarily caused by a lack of motivation, poor management, and insufficient training. Employees feel disengaged and less committed to work when they lack motivation or have too little work. Organizations that fail to create a culture of encouragement and reward achievements are more likely to experience productivity dips. Poor management practices, such as poor time management and project prioritization, can lead to frustration and unmotivation.
Insufficient training is also a significant factor, as 94 percent of workers would stay with a company if it invested in providing them with the necessary skills to perform their jobs effectively. Without proper training, employees may struggle to follow processes and procedures, leading to decreased productivity.
What makes the ocean least productive?
The productivity of aquatic ecosystems is constrained by two primary factors: limited light availability in deeper layers and limited nutrient availability in the ocean. Despite occupying 70% of the Earth’s surface, these ecosystems exhibit a productivity level of only 55 billion tons.
Where is ocean productivity lowest?
The overall pattern of ocean productivity varies with latitude, with low productivity in the tropics and subtropics due to nutrient limitation caused by strong, year-round thermocline and pycnocline. Large gyre systems in the North and South Atlantic also have low productivity. Abiotic factors like solar radiation and nutrients, and biotic factors like zooplankton predation may affect ocean primary productivity. Productivity varies with the season, locally and globally, and is a primary determinant of all biological productivity up the food web and trophic pyramid.
Satellite images, such as the Nimbus 7 satellite and the Coastal Zone Scanner, are used to explore these variations. The red end of the spectrum shows the highest productivity, while the blue/violet end is the lowest.
Why is biological productivity relatively low in the tropical open ocean?
The low biological productivity observed in the open ocean can be attributed to the scarcity of nutrients, which are essential for the growth and reproduction of producers. The higher levels of biological productivity observed in coastal areas, which receive surface runoff from land, can be attributed to the influx of nutrients from terrestrial sources.
Why is productivity low in tropical regions?
Ocean productivity is not solely determined by the region’s climate, but rather by factors such as temperature, nutrient availability, light, and ocean dynamics. Polar zones experience the highest primary productivity in summer, while temperate zones have two peaks in spring and fall. Tropical regions are nutrient-limited and show low productivity. Polar regions are light-limited in winter and only produce during late spring and summer. Northern temperate regions have a spring bloom and smaller autumn bloom due to the absence of thermocline.
Biological productivity is low in tropical regions due to the strong thermocline, while polar regions have low biological production due to lack of sunlight. Tropical waters have more sun but fewer nutrients, leading to less phytoplankton. Temperate waters have sun all year and more nutrients than tropical waters.
What factors limit productivity in the ocean?
The productivity of open oceans is constrained by a number of factors, including the availability of essential inorganic nutrients, water temperature, and turbidity. These factors are essential for maintaining the health and productivity of open oceans.
What limits productivity in tropical oceans and why?
The productivity of primary producers in tropical oceans is subject to influence from the availability of nutrients. It is notable that regions characterised by high levels of solar irradiance in the upper layers of the water column exhibit a surprising scarcity of nutrients.
What is the reason for low productivity in the ocean?
The Earth is composed of 70% ocean and 30% land. Sunlight is a major limiting factor in oceans, as it decreases the intensity of light, reducing the photosynthetic rate. This decrease in photosynthesis can hinder the development of plants and animals in aquatic environments. Phytoplanktons carry out the maximum primary production in oceans, while land is rich in mineral deposition, causing scarce nutrients and minerals. Small, floating autotrophic plants in oceans are the major producers, but their productivity is low due to their less vascular nature.
Terrestrial plants have developed advanced structures to enhance their photosynthesis capacity. The productivity of land is 170 billion tons, while the ocean’s productivity is only 55 billion tons. Marine waters offer maximum productivity through coral reefs, sea grasses, and brown algal beds. Cool waters also contain dense forests formed by kelps in the sublittoral zone of rocky coasts.
What is the leading cause of low productivity?
Low productivity can be attributed to various factors such as poor time management, unclear goals, inefficient processes, excessive workplace distractions, inadequate skills, low motivation, and high levels of stress or burnout. Examples of low productivity include consistently missing deadlines, subpar work output, frequent distractions, procrastination, frequent errors, and lack of progress despite significant effort.
The level of productivity measures the output or work accomplished within a given time frame, evaluated by evaluating the quantity, quality, and efficiency of completed tasks or projects. High productivity indicates that significant work is being done effectively and efficiently.
📹 Tropical Places That Can Freeze | Odd Geography
00:00 Where Tropical Cold Begins 02:00 Southern China 02:50 Southern Florida 04:45 Northernmost Tropical Climate 05:21 …
In some places of the neighbor state of Nuevo León you can also grow tropical plants peacefully until a random freeze wipes them out. Before the 2021 freeze there were over 110 coconut palms scattered around the city of Monterrey, after the freeze only a little more than a half survived. Some of them were in high altitudes in houses that surrounded the mountains of the city where “snow” fell which impressed me. A lot of tropical plants came back with all the amount of rain we’ve been getting since tropical storm Alberto. Our climate is mostly subtropical but when rain falls and the sun comes out, it feels like tropical.
One of the interesting questions I’ve tried to answer is the location of the highest latitude locations which have never frozen (in both hemispheres). For the northern, I’m almost certain that the answer is either Menton (the Wikipedia climate data shows it just barely has but I strongly suspect that the most protected and coastal microclimates have not, due to some circumstantial evidence of well established equatorial plants growing in the gardens there) and if not that then definitely the Azores which haven’t even gotten close even for the northernmost ones. For the southern, this is a lot harder, Mallacoota is the best candidate I’ve found yet that for sure never freezes, but I strongly suspect the more protected parts of the Corner Inlet and/or some islands present in the inlet do not freeze either (once again the data for a few locations here shows they just baaarely froze but these are along some more exposed sites). Cape Grim and King Island are other good candidates. Amazingly, the subpolar Auckland Islands have shockingly mild record minimum temps, and even support a population of tree ferns at a whopping 50 degrees south. Perhaps some ultra protected inlet could have never recorded a freeze? Either way, the temperate areas that don’t freeze are just as interesting as the tropical ones that do. Another fun one is coastal Norway, which while it definitely does freeze also has ridiculously mild winter temps, Tromsø has a higher record min temperature than Tallahassee and some places in the Lofoten archipelago like Vågan and Røst barely ever even graze past -10 C despite being above the arctic circle.
In Rio Grande Valley, there’s been 3 cold damming events that I can remember. There was one in December 2004 when it snowed during the night. One where it snowed the morning of December 8th, 2017. On that day, my sister and I went to the park to make a snowman. The snow had already been melting, but we managed to scrounge up enough for a 2 foot tall snowman. We adorned it with honey mesquite leaves. And, of course, the freeze of Valentines Day in 2021. That did such a number on the exotic plants of our community. A neighbor’s sugar date palm just died completely. Even many native trees froze to the ground, only to grow back later.
I would add North Vietnam to the list. The city of Lang Son is at about 21 Degrees North – well in the tropical zone. Yet just last year we had a major cold snap and had a major ice storm that coated everything in about 10mm of ice. Add to that, it’s only a few hundred feet above sea level. The mountain town of Sapa is about at 7,000 feet and it gets below freezing every year – it gets accumulated snow every few years. I was shocked when I moved to Hanoi because of how cold it gets in winter, 7-10C every year.
A particularly fascinating case in my opinion is eastern Australia. Mackay has recorded a freeze (just barely), while Mallacoota has not, despite Mackay being a borderline tropical climate and Mallacoota being solidly temperate, and the latter being a whopping 16 degrees of latitude further south. Both are along the eastern coastline, at sea level. The hardiness map of Australia is exceedingly weird, lots of little pockets of, well… not quite micro climates, but definitely weird local variations dotted all over the place.
Fun fact: About 1200 years ago, in the classic period, one of the most emblematic cities of maya culture, Palenque, had an abnormal season, so much that it left a trace of plants with frost scars, funnily enough if there’s one place you’d say can picture a jungle as accurately as possible it would be Palenque, home of jaguars, monkeys and tropical birds.
I’ve read about frosts in the state of Rondônia (northern region of Brazil) in the 60s, at low altitude and close to the equator, right in the middle of South America in a vast region fully hot tropical climate (Af/Am Koppen). Exactly as you mentioned, because from the extreme south of America to Rondônia is all plain, in fact a corridor between the Andes and the Brazilian highlands. As cold fronts are frequent, the phenomenon of “friagem” eventually reach the very north of the Amazon (crossing the equator) with subtropical temperatures (~10-15 ºC) for a few days up to 2 weeks Very interesting website and articles. Congratulations!
1:40 The alps play a big role in regulating the climate of northern Italy (the Po Valley). Compared to the oceanic climates on the other side of the alps, in northern Italy we have less warm winter warm spells caused by mild Atlantic currents, because of temperature inversion (Venice can have 1°C/3°C days with fog while Stuttgart in Germany has 6°C/10°C days), but also much less cold winter cold spells, with relatively dry -3°C/+3°C while Stuttgart experiences -7°C/-3°C extremes or colder. I would love it if you made a article about the climate of the Po valley, I think you could draw some climatic parallels with the US Midwest even if our climate is a lot less extreme (Milan has similar avg annual temperature to Kansas City, with warmer winters, colder summers, and a storm season in summer which can cause violent storms and hail but rarely tornadoes, contrary to the Midwest)
I enjoy this type of content. Thanks for sharing! I have always assumed that tropical areas that freeze, are considered subtropical, like where I am in Northern FL. I have found that some of the traditional Southern plants are extremely cold hardy, like the Southern Magnolia, Sable Palm and Live Oak for example. They can handle subzero (subzero F) temps in many cases.
Many plant species have adapted to survive these cold fronts. In Tamaulipas there is a tropical plant/palm that is called chamedorea radicallis and it can take snow. I grow it in Texas and New Mexico and it thrives even in harsh winters. There are many other plants that have not been discovered yet or tested for cold hardiness.
you’re doing great work. i’ve always wondered why there’s all these weird, asymmetrical weather patterns everywhere or why the northern latitudes are dominated by conifers. no one i know is that curious about them or expresses any interest in these things. so it is vindicating to me to see you analyze these phenomena that i previously assumed was a false perception on my part or had obvious answers i was too dull to see.
Finding unexpected climates is a topic that has always fascinated me. Therefore, I cannot help but mention that the coldest and most tropical country at the same time must be Peru. Its southernmost point is at latitude 18°S (which would correspond to Jamaica in the north). Even so, 70% of all tropical glaciers in the world are in Peru, precisely because of the combination of the high altitude of the Andes and the humidity coming from Ecuador. Bolivia, for example, being a little further south has also the altitude and a geography within the tropics, but very few glaciers since the areas close to the limits of the tropics have less humidity. Another reason for Peru is to find frozen areas at sea level due to the Humboldt Current which is the coldest in the world (not the coldest in absolute value, but in comparison with the temperature of the Pacific at those latitudes). The Peruvian coasts are usually 10 degrees colder than the ocean waters, this causes hail to occur at only 100-200 AMSL and near the sea at a latitude as “warm” as 12°S (it happened in Lima in 2021) or temperatures that can reach 0.6°C near the sea which is the coldest reported in the coastal plain. It would be interesting to expand on the topic of the very strange and cloudy climate that the coasts of Peru and Angola have due to their cold currents.
While the extremes and frequency can not match those in the Americas, especially North America, north eastern Australia can occasionally get random freezing spells north of the Tropic of Cancer. I suppose the great dividing range also drives this, but given the milder climate of Australia generally and the low height of those mountains, can not generate the same effect as the Americas.
You can research about the great cold wave of July 1975 in South America, to this day one of the coldests “friagens” to reach Central and Northern Brazil, with frosts being recorded in areas within the Amazon. Also, an unique phenomenon that occurs only in South America is that a cold front can reach the Northern Hemisphere through the Amazon, as it has happened before many times with the cold reaching as north as 10˚N in Venezuela.
It’s funny, I was just reading about phenomena like this! I’ve always been fascinated by tropical plants, as I live in a temperate region. So, I read a lot about tropical plants that can survive cold weather. There are a surprising number of plants from the tropcis that are invasive in temperate regions because they have adaptaions for surviving the occasional frost!
I lived in and around both West Palm Beach and Port St. Lucie in Florida as a kid, and i remember snow falling on a beach somewhere in that area back in about 2002-2003. I was used to New York winters so it was a comically small amount of snow in comparison, and none of it stuck, but nonetheless it was snowing right on the beach in south Florida
Im from Santa Cruz, Bolivia. Winters can be harsh, a single surazo in the middle of winter can stay up to 10 continuous days with temperatures not exceeding 16°C, with thermal sensation surounding 6-10°. Occasionally frost can occur and along with it thermal sensation at -5°C, it blows the minds of foreigners as they don’t expect such cold temperatures in a ‘tropical’ place. Normally 1 or 2 ‘surazos’ hit Santa Cruz every month from April to August, a particularly harsh winter could make the capital city classify as Humid subtropical Cwa climate instead of Tropical Savanna Aw.
in java island dieng, wonosobo, indonesia and some part of west and east java also have freeze season that occur only one month in a year mostly august where you can found ice cube and freeze leafs all over the place, it’s probably also the cold wind, the weird part is that Indonesia is equator most of your subject in article and reference study are not even that close to equator such as sahara, peru, Australia, etc are closer to desert/dry climate.
It’s not like tropical forests in these locations don’t also experience setbacks after getting a direct hit from a major hurricane. Although some tropical plants might not survive a freeze, the larger forest can still respond quickly to disturbance. These areas may also have a winter dry season, which in theory would allow some plants to go semi-dormant. In Ohio, a hardy southern magnolia (Magnolia grandiflora) occasionally dies back to the ground after a severe winter. Since the tree tolerates fire, it simply re-sprouts from the roots. It’s not like the tree cares whether it was a fire or a freeze, as the plant’s response is the same. Black locust (Robinia pseudoacacia) is very prone to late spring frost damage, but it’s not super relevant as the tree will quickly leaf out again and outgrow the damage.
I live just on the Tropic of Capricorn in Central Queensland. This winter it got down to freezing twice. Interesting you mentioned lizards. I used to live in the Cootamundra area in NSW where the temperature gets down to -7 sometimes. There is a large lizard called the Perentie that seems to live quite well there. Maybe it has adapted to the cold. You would expect to see them live in the tropics rather than a cold climate, although we used to have heaps of snakes in the summer, so similar, I guess.
This is such a fascinating topic, I learned so much from this article! Another case of tropical flora surviving occasional cold snaps that i’ve always found interesting is Spanish Moss (a bromeliad) in the southern US. It’s northern limit seems to be coastal Virginia, but still, very impressive for a tropical epiphyte. I’m so glad I found your website, can’t wait to binge the rest of your articles!
I’m from Mobile Alabama, not tropical by any means, but a similar hot climate to New Orleans. Visitors come from up north to escape winter. Usually it’s in the 50s during the day and 30s or 40s at night, which definitely catches many visitors off guard. Occasionally, it does snow and temperatures dip into the teens.
One of those rare southern snowfall near the geographical limit explained in the article was the cause of the downfall of the coffee plantations/indutry in Cuetzalan acordign to the locals I met on one of my recent trips there 🙁 When I learend that they have seen snow it blew my mind and was the recent I clicked on the article… I wanted to know how a place thats warmer and “lower” than my 2000+m in altitude city has seen snow with far more regularity than my typical high altitude Mexican city xD
I lived in Palm Beach County Florida in the 1970s and 1980s. The Freeze Line runs just South of Lake Okeechobee across the State. In January 1971, we had a record low of 28 degrees. All the citrus groves had their sprinklers running and there were ice cycles hanging from the trees. I remember the snow in 1977, we were in class when the snow started. We were in disbelief perusal it fall. We matched the 28 degrees December of 1989. In that year, the cold lasted a few days longer than the one in 1971 and killed off the leaves on most of the trees.
I live in the subtropical rainforest region of Argentina, we fight against heat and humidity but we can never forget to take measures against a posible freezing because the damage can be truly devastating. Sometimes the ice falling can be so big that can killed a person if it hits the head. In my province we can have up to 41 c in summer and usually tame winters but they can surprise you with down to -3 C, even worse in the towns near hills formations (we are in the transition between the argentine plain an the mountainous region of Brazil). We protect our crops, cars and cattle against the frezee with both physical measures and taking insurance but usually is not enough. Here we called what you mentioned as Friaje as La Helada (literally The Icing)
In Australia, there have been historical recordings of snow in areas of the great dividing range from up to Mackay Queensland (specifically eungella rainforest) which is located above the capricorn belt and 900m in elevation. It can get pretty cold at night there even nearing summer. Queensland rarely gets any snow unless you are near the border of New South Wales which is 900km away.
1:23 I can confirm. I live in Southern Michigan and my brother lives in Southern Wisconsin. Its always far colder there when I visit him during winter compared to where I live in Michigan despite both of the cities we live in being roughly the same latitude. Wisconsin gets BRUTALLY cold in the winter. I am talkin weeks of single digit and negative temperatures while our temperatures are a more consistent high 20s low 30s usually.
You have to take the koppen climate classification with a grain of salt. It would have you believe that much of continental western montane Mexico is Mediterranean climate, with a dry summer, wet winter. This is completely false- it has a very intense summer rainy season and dry to arid winters, but the seasonal lag is such that the primitive cutoffs used by koppen to classify fail. Likewise for the spot of Montana that has an oceanic climate- sorry, but nothing that sees -30F temperatures can be considered oceanic.
I lived in Texas during one of the hard freezes! It did not get above freezing for 5 whole days in Corpus Christi! Also, on the topic of this article, I personally believe that the Koppen Climate Classification System should be updated with some modifications of terminology in regards to tropical and subtropical climates. For example, the regions which are considered “tropical” that very rarely freeze could alternatively be called “subtropical” instead due to these places indeed actually freezing on very rare occasions. Alternatively, the Koppen Climate Classification System could add the term “pseudo-tropical” to denote tropical regions in which frost does occur on very rare occasions.
Although here in Argentina there are no truly tropical areas, in the north which is the closest, some frosts usually occur on the coldest winter days, in fact there is a record of -10 degrees Celsius below zero in the province of Chaco at 100 meters above sea level and at a latitude of 24 degrees south. I do not know of such a low temperature at those latitudes and elevations anywhere else in the southern hemisphere. Further south in the Pampas region those temperatures are much more normal, in July 2024 I experienced -7 degrees below zero on the outskirts of Buenos Aires and reached -11 in more continental areas of the province.
The New Guinea (Pupua) has a rainforest next to a glacier (Carstensz Glacier). It is one of the most isolated, geographically varied and culturally dense – due to its harsh terrain – places in the world. Its amongst the most language dense places in the world thanks new languages popping up due to the isolated pockets of tribes living by themselves for years. Its also the second largest island in the world after Greenland. Its a shame what is happening to the west of the island, it should one island.
I’ve never heard of the 1977 snow/frost event in Florida but it sounds a lot like the great freeze of July 1975 in Brazil. This event was legendary with a minimum of -5ºC in Curitiba (my home city, at 25ºS – 900m) and accumulating snow, as well as a very intense frost that killed most coffee plants in Paraná and São Paulo states with freezing temperature reaching likely latitudes of 20ºS inland.
The Challenger Disaster happened because it was so cold in Florida and many execs and the president were impatient to launch. Icicles formed on the rocket, and the o rings which are supposed to be flexible, froze and became very rigid, allowing a gap from the rocket boosters through which burning fuel was being released, eventually damaging the rocket through a snowball effect until the superstructure failed.
According to the Kopen climate New York City and long Island have a humid subtropical climate. UT used to be much colder. We used to have snow on the ground for a mibth. Now snow doesn’t last long but a lot if tropical plants can grow here well into autumn. Before being taken insude. Autumn us the nicest season having temperatures in the 70s during the day and upper50 s at nught.
I’m not sure if this is a tropical region but Dar Es Salaam in Tanzania on Africa’s east coast has been known to get snowfall which I think is interesting. A lot of east africas major cities have actually been know to receive snowfall but this is due to the higher elevations of places like Addis Ababa, Nairobi, and Arusha. However Dar Es Salaam lies at sea level which I think is interesting.
Here in Indonesia, an archipelago nation right on equator (Indonesia lies between 7 degrees North-10 degrees South), in many towns in the highlands, freezing temperatures are a seasonal norm. Example: Dieng village (altitude: 2000 m) below Mt. Prau (2500 m) in Java, there are 1-2 weeks every year in the SUMMER where it goes 0, lowest record -10. But how come in Summer? coz ummer = dry season. In “winter”/monsoon, rain/humidity makes it warmer. You should try researching this more because this happens on islands, not continents like the examples
Informative and interesting to be sure, but can you please define “tropical?” Having lived alongside the Everglades and grown lychee, mangoes and bananas, the definition we used is “never frosts” and therefore we were subtropical, as though rare and never hard (and so not a serious threat to our orchards,) it could frost in Homestead. Another definition is between the tropics, and you seem to be using a third, mean temp of the coolest month >18 deg C. Admittedly I’m getting bogged down in the details, as after perusal the article I know what you’re getting at, and I can’t suggest a better way to package it, but really being tropical has nothing to do with it. Most equatorial regions with regular freezes at low altitude due to particular geographic circumstances? Not exactly clickbait, that…
hi. this is kinda off topic, but why are there few to none temperate deciduous trees in the northern indian plains, even though it has a humid subtropical climate and gets temps close to freezing almost every winter? other humid subtropical regions in the world at similar latitudes have lots of temperate deciduous trees
Stuart Florida doesn’t have a tropical rain forest climate. The defining characteristic of this climate is evenly distributed rainfall. Stuart gets 2-3 inches of rain in winter and 7-10 inches in the summer months. Just because you pulled this information from Wikipedia doesn’t mean it’s true. Do your own research