Con buona pace dei Popoli del Mare

LA  SICCITA'  CAUSO'  IL  COLLASSO  DELL' ETA'  DEL  BRONZO.

Drought drove collapse of Late Bronze Age civilizations

commento personale: è più che evidente come il Consenso

Scientifico Internazionale si sia ormai definitivamente

orientato verso l'inesistenza accertata dei cosiddetti 'popoli 

del mare' (nel senso inteso da Maspero 300 anni fa) e della 

inconsistenza della loro  gloriosa epopea guerresca: questo, 

di conseguenza, fa inesorabilmente cadere tutto il 

farneticante castello di carte costruito da alcuni scrittori 

autodidatti sardi intorno ad una presunta presenza, tra 

essi, dei fantomatici "shardana", con tutto ciò che ne 

consegue logicamente: una Storia Sarda più vera restituita 

finalmente ai Sardi...

LA PALEOCLIMATOLOGIA DIMOSTRA CHE FU LA SICCITA' A PRODURRE IL COLLASSO DELLA FINE DELL'ETA' DEL BRONZO, VERSO IL 1300 A.C. NELLE FINO AD ALLORA FIORENTI CIVILTA' DEL MEDITERRANEO ORIENTALE: LA RICERCA, DI DAVID KANIEWSKI (DELL'UNIVERSITA' DI TOLOSA IN FRANCIA, INSIEME CON COLLEGHI DA ALTREI ISTITUTI), E' PUBBLICATA SUL NUMERO DEL 14 DI AGOSTO DELLA RIVISTA SCIENTIFICA PLOS ONE, CON ACCESSO LIBERO.

 Climate change may have driven the collapse of once-flourishing Eastern Mediterranean civilizations towards the end of the 13th century BC, according to research published August 14 in the open access journal PLOS ONE by David Kaniewski from the University of Paul Sabatier, Toulouse, France and colleagues from other institutions.

LA REGIONE SULLA QUALE SONO STATI CONDOTTI GLI STUDI: IL LAGO SALATO, CON HALA SULTAN TEKKE NELLO SFONDO, (CIPRO).
This is the region where the study was performed (Salt Lake and the Hala Sultan Tekke in the background) [Credit: Geological Survey of Belgium/ David Kaniewski]

LE ANTICHE CIVILTA' DEL MEDITERRANEO ORIENTALE SI TROVAVANO IN VARIE SEDI CONFINANTI DELLE REGIONI COSTIERE DELL'EUROPA MERIDIONALE E DELL'ASIA OCCIDENTALE,  OLTRE CHE DI ALCUNE ISOLE (GRECIA E SIRIA SONO L'OGGETTO DEL CAMPIONAMENTO DEL PRESENTE STUDIO). LE GRANDI POTENZE NOTE DI ALLORA ERANO SETTE: ALCUNE DI ESSE ERANO IN SITUAZIONE DI PRECARIO EQUILIBRIO PER LA LORO GRANDE DIPENDENZA DAI GRANDI PAESI AGRICOLI PRODUTTORI. TUTTE SOFFRIRONO UNA GRAVISSIMA CRISI, CHE CONDUSSE AL LORO COLLASSO, SUL QUALE E' STATA ROMANZATA L'EPOPEA (IN MASSIMA PARTE IMMAGINARIA) DEI COSIDDETTI  "POPOLI DEL MARE".

Ancient civilizations flourished in regions of the Eastern Mediterranean such as Greece, Syria and neighboring areas, but suffered severe crises that led to their collapse during the late Bronze Age. 

SONO STATI STUDIATI GRANI DI POLLINE OTTENUTI DAI SEDIMENTI DI UN ANTICO LAGO DELLA REGIONE, PER POTERE OTTENERE DATI CERTI SULLE MODIFICAZIONI AMBIENTALI DELL'EPOCA E RICAVARNE LA PROVA DEI CAMBIAMENTI CHE PRODUSSERO LA CRISI.

Here, researchers studied pollen grains derived from sediments of an ancient lake in the region to uncover a history of environmental changes that likely drove this crisis. 

LE MODIFICHE NEL CONTENUTO DEGLI ISOTOPI DI CARBONIO NEL MEDITERRANEO ORIENTALE E LE SPECIE VEGETALI LOCALI INDICANO CHE IL LAGO SALATO UN TEMPO ERA UN FIORENTE PORTO MARINO, CHE SI E' GRADUALMENTE INTERRATO FINO A RISULTARNE UN LAGO SALATO ISOLATO DAL MARE.

Shifts in carbon isotopes in the Eastern Mediterranean and in local plant species suggest that this lake was once a flourishing harbor that gradually dried into a land-locked salt lake. 

PIANTA DI CIPRO, CON VISTA DEL LAGO SALATO DELLA BAIA DI LARNAKA (HALA SULTAN TEKKE)
Map of Cyprus with an overview of the Larnaca Salt Lake (Hala Sultan Tekke) in the Larnaca Bay [Credit: doi:10.1371/journal.pone.0071004.g001]

DI CONSEGUENZA, LA MANCANZA DI RACCOLTO PORTO' ALLA CARESTIA IN MOLTI PAESI, MOTIVANDO RIPETUTE INVASIONI DI EMIGRANTI CHE INVASERO LE REGIONI LIMITROFE ED INFINE OVUNQUE SI PRODUSSE  IL COLLASSO POLITICO, AMMINISTRATIVO ED ECONOMICO  DI TUTTE LE 'POTENZE' DEL MEDITERRANEO ORIENTALE, VERSO LA FINE DELL'ETA' DEL BRONZO.

As a result, crop failures led to famines, repeated invasions by migrants from neighboring regions and eventually, the political and economic collapse of the Eastern Mediterranean civilizations at the end of the late Bronze Age.

METTENDO INSIEME QUESTI DATI SCIENTIFICI E QUELLI ARCHEOLOGICI OTTENUTI DALLE TAVOLETTE IN CUNEIFORME E LA CORRISPONDENZA TRA I RE DI ALLORA, I RICERCATORI SUGGERISCONO  CHE LA CRISI DEL BRONZO FINALE FU UN EVENTO COMPLESSO E MULTIFATTORIALE, COMPRENDENTE  SICCITA', CARESTIA, LOTTE POLITICHE, GRAVI DISAGI ECONOMICI E SOCIALI, INVASIONI DI EMIGRANTI ED ALTRO ANCORA: NON PUO' ESSERE SPIEGATO CON UN SEMPLICE EVENTO SINGOLO.

Combining this data with archaeological evidence from cuneiform tablets and correspondence between kings, the researchers suggest that the late Bronze Age crisis was a complex, single event comprised of climate change-induced drought, famines, sea-borne invasions and political struggles, rather than a series of unrelated events. 

IN CONCLUSIONE, SI SOTTOLINEA LA SENSIBILITA'  AL CLIMA ED AI FATTORI AMBIENTALI DI QUESTE ANTICHE SOCIETA' BASATE SULL'AGRICOLTURA, DEMISTIFICANDO LA CRISI CHE CONDUSSE ALLA LORO FINE.

They conclude that this event underlines the sensitivity of these agriculture-based societies to climate, and demystifies the crisis that led to their end.

Source: Public Library of Science [August 15, 2013]

IN DIPENDENZA DEL CLIMA

Climate change blamed for 

Harappan collapse

A new study combining the latest archaeological evidence with state-of-the-art geoscience technologies provides evidence that climate change was a key ingredient in the collapse of the great Indus or Harappan Civilization almost 4000 years ago. The study also resolves a long-standing debate over the source and fate of the Sarasvati, the sacred river of Hindu mythology. 

[Credit: Woods Hole Oceanographic Institution]

Once extending more than 1 million square kilometers across the plains of the Indus River from the Arabian Sea to the Ganges, over what is now Pakistan, northwest India and eastern Afghanistan, the Indus civilization was the largest—but least known—of the first great urban cultures that also included Egypt and Mesopotamia. Like their contemporaries, the Harappans, named for one of their largest cities, lived next to rivers owing their livelihoods to the fertility of annually watered lands. 

"We reconstructed the dynamic landscape of the plain where the Indus civilization developed 5200 years ago, built its cities, and slowly disintegrated between 3900 and 3000 years ago," said Liviu Giosan, a geologist with Woods Hole Oceanographic Institution (WHOI) and lead author of the study published the week of May 28 in the Proceedings of the National Academy of Sciences. "Until now, speculations abounded about the links between this mysterious ancient culture and its life-giving mighty rivers." 

Today, numerous remains of the Harappan settlements are located in a vast desert region far from any flowing river. In contrast to Egypt and Mesopotamia, which have long been part of the Western classical canon, this amazingly complex culture in South Asia with a population that at its peak may have reached 10 percent of the world's inhabitants, was completely forgotten until 1920's. Since then, a flurry of archaeological research in Pakistan and India has uncovered a sophisticated urban culture with myriad internal trade routes and well-established sea links with Mesopotamia, standards for building construction, sanitation systems, arts and crafts, and a yet-to-be deciphered writing system. 

"We considered that it is high time for a team of interdisciplinary scientists to contribute to the debate about the enigmatic fate of these people," added Giosan. 

Once extending more than 1 million square kilometers across the plains of the Indus River from the Arabian Sea to the Himalayas and the Ganges, over what is now Pakistan, northwest India and eastern Afghanistan, the Indus civilization was the largest—but least known—of the first great urban cultures that also included Egypt and Mesopotamia. Named for one of their largest cities, the Harappans relied on river floods to fuel their agricultural surpluses. Today, numerous remains of the Harappan settlements are located in a vast desert region far from any flowing river [Credit: Liviu Giosan, Woods Hole Oceanographic Institution; Stefan Constantinescu, University of Bucharest; James P.M. Syvitski, University of Colorado]

The research was conducted between 2003 and 2008 in Pakistan, from the coast of the Arabian Sea into the fertile irrigated valleys of Punjab and the northern Thar Desert. The international team included scientists from the U.S., U.K., Pakistan, India, and Romania with specialties in geology, geomorphology, archaeology, and mathematics. By combining satellite photos and topographic data collected by the Shuttle Radar Topography Mission (SRTM), the researchers prepared and analyzed digital maps of landforms constructed by the Indus and neighboring rivers, which were then probed in the field by drilling, coring, and even manually-dug trenches. Collected samples were used to determine the sediments' origins, whether brought in and shaped by rivers or wind, and their age, in order to develop a chronology of landscape changes. 

"Once we had this new information on the geological history, we could re-examine what we know about settlements, what crops people were planting and when, and how both agriculture and settlement patterns changed," said co-author Dorian Fuller, an archaeologist with University College London. "This brought new insights into the process of eastward population shift, the change towards many more small farming communities, and the decline of cities during late Harappan times." 

The new study suggests that the decline in monsoon rains led to weakened river dynamics, and played a critical role both in the development and the collapse of the Harappan culture, which relied on river floods to fuel their agricultural surpluses. 

From the new research, a compelling picture of 10,000 years of changing landscapes emerges. Before the plain was massively settled, the wild and forceful Indus and its tributaries flowing from the Himalaya cut valleys into their own deposits and left high "interfluvial" stretches of land between them. In the east, reliable monsoon rains sustained perennial rivers that crisscrossed the desert leaving behind their sedimentary deposits across a broad region. 

The research was conducted between 2003 and 2008 in Pakistan, from the coast of the Arabian Sea into the fertile irrigated valleys of Punjab and the northern Thar Desert. In the field, the researchers probed the landforms constructed by the Indus and neighboring rivers by drilling, coring, and even manually digging trenches (shown here). Collected samples were used to determine sediment origin, whether brought in and shaped by rivers or wind, and sediment age, in order to develop a chronology of landscape changes [Credit: Peter D. Clift, School of Geosciences, University of Aberdeen, UK]

Among the most striking features the researchers identified is a mounded plain, 10 to 20 meters high, over 100 kilometers wide, and running almost 1000 kilometers along the Indus, they call the "Indus mega-ridge," built by the river as it purged itself of sediment along its lower course. 

"At this scale, nothing similar has ever been described in the geomorphological literature," said Giosan. "The mega-ridge is a surprising indicator of the stability of Indus plain landscape over the last four millennia. Remains of Harappan settlements still lie at the surface of the ridge, rather than being buried underground." 

Mapped on top of the vast Indo-Gangetic Plain, the archaeological and geological data shows instead that settlements bloomed along the Indus from the coast to the hills fronting the Himalayas, as weakened monsoons and reduced run-off from the mountains tamed the wild Indus and its Himalayan tributaries enough to enable agriculture along their banks. 

"The Harappans were an enterprising people taking advantage of a window of opportunity – a kind of "Goldilocks civilization," said Giosan. "As monsoon drying subdued devastating floods, the land nearby the rivers - still fed with water and rich silt - was just right for agriculture. This lasted for almost 2,000 years, but continued aridification closed this favorable window in the end." 

In another major finding, the researchers believe they have settled a long controversy about the fate of a mythical river, the Sarasvati. The Vedas, ancient Indian scriptures composed in Sanskrit over 3000 years ago, describe the region west of the Ganges as "the land of seven rivers." Easily recognizable are the Indus and its current tributaries, but the Sarasvati, portrayed as "surpassing in majesty and might all other waters" and "pure in her course from mountains to the ocean," was lost. Based on scriptural descriptions, it was believed that the Sarasvati was fed by perennial glaciers in the Himalayas. Today, the Ghaggar, an intermittent river that flows only during strong monsoons and dissipates into the desert along the dried course of Hakra valley, is thought to best approximate the location of the mythic Sarasvati, but its Himalayan origin and whether it was active during Vedic times remain controversial. 

Archaeological evidence supports the Ghaggar-Hakra as the location of intensive settlement during Harappan times. The geological evidence—sediments, topography— shows that rivers were indeed sizable and highly active in this region, but most likely due to strong monsoons. There is no evidence of wide incised valleys like along the Indus and its tributaries and there is no cut-through, incised connections to either of the two nearby Himalayan-fed rivers of Sutlej and Yamuna. The new research argues that these crucial differences prove that the Sarasvati (Ghaggar-Hakra) was not Himalayan-fed, but a perennial monsoon-supported watercourse, and that aridification reduced it to short seasonal flows. 

By 3900 years ago, their rivers drying, the Harappans had an escape route to the east toward the Ganges basin, where monsoon rains remained reliable. 

"We can envision that this eastern shift involved a change to more localized forms of economy: smaller communities supported by local rain-fed farming and dwindling streams," said Fuller. "This may have produced smaller surpluses, and would not have supported large cities, but would have been reliable." 

Such a system was not favorable for the Indus civilization, which had been built on bumper crop surpluses along the Indus and the Ghaggar-Hakra rivers in the earlier wetter era. This dispersal of population meant that there was no longer a concentration of workforce to support urbanism. "Thus cities collapsed, but smaller agricultural communities were sustainable and flourished. Many of the urban arts, such as writing, faded away, but agriculture continued and actually diversified," said Fuller. 

"An amazing amount of archaeological work has been accumulating over the last decades, but it's never been linked properly to the evolution of the fluvial landscape. We now see landscape dynamics as the crucial link between climate change and people," said Giosan. "Today the Indus system feeds the largest irrigation scheme in the world, immobilizing the river in channels and behind dams. If the monsoon were to increase in a warming world, as some predict, catastrophic floods such as the humanitarian disaster of 2010, would turn the current irrigation system, designed for a tamer river, obsolete."  

Source: Woods Hole Oceanographic Institution [May 28, 2012]