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Russia: prospettive commerciali- KanAz e MAZ

(chi non desidera questo post è pregato di comunicarlo a geografia2013@libero.it. I commenti possono essere inviati tramite la casella Commenti del post stesso . Massimo Coltrinari)

Key Vords: Russia | Commerciale e altri veicoli | Daimler

10 dicembre 2013

KamAZ e MAZ sono state rimuginando una fusione per anni, ma ora le pressioni di mercato sono in aumento.

Per tre anni più grande produttore russo di autocarri pesanti, KAMAZ, è stato in trattative per prendere in consegna un altro sopravvissuto dell'era sovietica, con sede in Bielorussia MAZ. I politici, che sono midwifing la fusione, affermare che esso può essere finalizzato entro la fine del 2013, ma dovranno superare diverse complicazioni prima. Uno è che KamAZ potrebbe presto ottenere un nuovo azionista importante, dopo Daimler della Germania ha ricevuto il via libera da parte delle autorità russe della concorrenza ad assumere una partecipazione di blocco in camion-maker a base di Tatarstan.

Non che Daimler si sarebbe opposto alla fusione in teoria. KamAZ è il secondo più grande produttore di veicoli commerciali in Russia, dietro GAZ Group, che rende furgoni e autocarri leggeri, e davanti a ZIL, che è stato mantenuto in vita con infusioni di denaro da parte del governo municipale di Mosca. La fusione con MAZ, che vende circa l'80% della sua produzione nel mercato russo, non solo avrebbe incrementare la quota di mercato complessiva di KAMAZ, ma aumentare la gamma dei suoi prodotti.MAZ è forte nella produzione di rimorchi, che fino ad ora ha fatto solo il 5% della produzione KamAZ.

Ci sono un sacco di difficoltà politiche, tuttavia. Anche se la Bielorussia è parte di un soggetto politico conosciuto come lo Stato della Russia e Bielorussia Unione, i due paesi non sono solo sovrano, ma molto diversa. La Russia ha sviluppato un post-sovietico economia wild-Est dominato da conglomerati statali predatori, mentre la Bielorussia, che solo fra le repubbliche ex-sovietiche mantiene la sua bandiera sovietica, è gestito da un dittatore populista che sta cercando di mantenere una economia comunista-era .

Non ha funzionato bene. Una crisi economica prolungata ha indotto la Bielorussia a privatizzare i propri beni industriali, con le aziende e gli imprenditori emergenti come principali acquirenti russi. Tuttavia, il governo di Minsk è alla guida di un affare piuttosto difficile, considerando che questo è una vendita angoscia. Vuole l'accordo per essere strutturato come una fusione tra pari, anche se il valore di KAMAZ, la cui capitalizzazione di mercato è di circa Rb38bn (US $ 1,2 miliardi), supera il valore stimato di MAZ di ben il 50%.

La fusione in sé può non essere facile. MAZ è ancora eseguito su un modello di business sovietico, con strati eccesso di personale, la produttività mediocre e salari molto bassi, ma sicuri. L'azienda ha riferito di dieci volte il numero di ingegneri MAN, il produttore di camion tedesco. Manager russi sono suscettibili a chiedere una maggiore produttività, automatizzare molti processi attualmente eseguiti a mano e attuare licenziamenti.

Pressioni del mercato

A meno che i manager MAZ e leader politici Bielorussia affrettano a completare l'affare, che potrebbe presto scoprire che la loro mano è stata sostanzialmente indebolita.L'anno prossimo, canone di utilizzo della Russia, che attualmente è imposto solo su autoveicoli importati, verrà esteso a quelli nazionali, nonché, come stabilisce l'Organizzazione mondiale del commercio. Entro il 2019 la Russia sarà inoltre obbligato ad abbandonare la sua tariffa del 25% sui veicoli importati al 15%.

Che esporrà i produttori nazionali e di fabbricazione russa marche estere, che conto corrente per circa il 53% del mercato dei veicoli commerciali, a una maggiore concorrenza. Sarà probabilmente anche intaccare la quota di mercato di camion e autobus Bielorussia-fatti, che sono trattati come domestico in Russia perché i due paesi, insieme con il Kazakistan, appartengono all'Unione doganale. Essere esentati dalla tassa di riciclaggio ha funzionato come un sussidio per MAZ, ma ora i camion provenienti dalla Bielorussia dovrà competere con veicoli importati su un piano di parità.

I problemi saranno aggravati dallo stato volatile del mercato dei veicoli commerciali della Russia. Le vendite sono crollate dopo che la Russia è stata colpita duramente dalla crisi finanziaria globale, ma poi triplicate tra il 2009 e il 2011, di oltre 120.000 unità. Il mercato stabilizzato lo scorso anno, registrando solo una crescita modesta, e si infilò nel 2013 ancora una volta come l'economia ha ristagnato. Il mercato dei veicoli pesanti (15-45 tonnellate) si è ridotto di un terzo nel periodo gennaio-settembre e le previsioni per gli anni vicini sono stati ridotti notevolmente.

In un mercato in crisi, KamAZ ha eseguito relativamente bene. Le sue vendite denominati in rubli sono diminuiti solo del 6%, a Rb77.2bn, nei primi tre trimestri del 2013. Ha prodotto circa 27.000 camion e kit di montaggio e la sua quota di mercato è cresciuta al 45%, da circa il 40% nello stesso periodo del 2012. Inoltre, all'inizio di dicembre, la società ha iniziato la produzione di massa del suo nuovo 60-ton KAMAZ-5409-lunga distanza autotrasportatore, progettato in collaborazione con Daimler e dotato di una comoda cabina Mercedes-Benz. Dopo un lancio lento quest'anno, si prevede di vendere 2.000 unità nel 2014 e di incrementare la produzione di 10.000 all'anno presto, afferrare questo segmento del mercato russo.

Eppure la concorrenza interna è in aumento anche. Alcuni produttori russi stanno iniziando ad assemblare veicoli commerciali stranieri. ZIL in particolare, nel tentativo di ottenere una nuova prospettiva di vita, sta lavorando con una varietà di produttori internazionali per assemblare i loro camion e autobus. I suoi partner sono Fiat (Italia), Hyundai (Corea del Sud) e Dongfeng (Cina). I suoi autobus saranno in concorrenza con i prodotti MAZ direttamente, e può muoversi nel segmento autocarro pesante pure. Nel frattempo, Scania (Svezia), che ha uno stabilimento a San Pietroburgo, ha annunciato l'anno scorso che investirà circa US $ 90 miliardi fino al 2015 e prevede di raddoppiare la produzione in Russia da 3.500 unità a 7.000 unità.

Anche KamAZ può diventare una marca straniera - ad un grado. Daimler, che detiene attualmente il 11% della società, è stata autorizzata dal Servizio federale di monopoli di acquisire una partecipazione di blocco. Una sede a Cipro consorzio degli investitori che attualmente detiene una quota del 25% si dice di vendere una parte della sua partecipazione alla casa automobilistica tedesca, che è il più grande produttore di autobus e camion del mondo. Altri azionisti sono Russian Technologies, un industriale e la difesa conglomerata di proprietà dello Stato guidato da un amico di Vladimir Putin Sergey Chemesov (49,9%), e la Banca europea per la ricostruzione e lo sviluppo (4%).

Tutte queste tendenze indicano un consolidamento parziale del mercato degli autocarri pesanti russo e una più forte concorrenza, che potrebbe spremere poveri, i giocatori di bassa qualità come MAZ meno che non trovi un partner profonda buca. La fusione con KamAZ - e di farlo presto - potrebbe diventare una necessità vitale per MAZ, fintanto che Daimler ed i politici possono concordare un accordo.

Fonte: Industria Briefing

Il picco dell'acqua prossimo venturo

Di

Paolo Migliavacca.

Sintesi

Solo il 2,6% dell’acqua presente sulla Terra è dolce. Attualmente l’umanità ne consuma oltre 4 mila km2 annui: 400 per usi domestici, 1200 per usi industriali e ben 2500 per usi agricoli. La disponibilità è inoltre geograficamente assai squilibrata: un abitante dei paesi industrializzati dispone in media di circa 300 litri d’acqua potabile al giorno, mentre chi vive in quelli sottosviluppati meno di un decimo, da 10 a 30. Detto altrimenti, l’11% della popolazione mondiale consuma l’88% dell’acqua disponibile. Ciò costituisce il vero nucleo del problema idrico , in grado di far deflagare conflitti interstatuali per il controllo delle risorse idriche. Questa scarsità è distinta ad accentuarsi a causa dei tassi di sviluppo economico e della presente demografia. Poiché 276 grandi laghi o corsi d’acqua mondiali (i cui bacini riguardano il 46% delle terre emerse, metà della popolazione planetaria e 148 dei 204 Paesi del mondo sono ripartiti tra due o più Paesi rivieraschi, il rischio di conteziosi internazionali è significativo. La guerra per l’acqua non è però un esito obbligato: vari accordi di cooperazione sopranazionale in materia fluviale hanno infatti continuato ad operare anche in presenza di uno stato di belligeranza tra i Paesi firmatari.

“Nomos & Khaos. Rapporto Nonisma 2012-2013 sulle prospettive economico-strategiche. Osservatorio Scenari Strategici e di Sicurezza. (approfondimenti ed info:www. Nonimasma.it)

 

Trude Peterson: nota

Spazio: sicurezza e prospettive

E 'necessario fornire delle definizioni chiare e precise di alcuni termini che verranno utilizzati in questa trattazione. Lo spazio è tutto ciò che si pone al di là dell’ambito aeronautico, definito legalmente come la distanza che è in grado di percorrere una molecola prima che questa si scontri con un’altra, il che avviene più o meno ad un’altezza di 100 km. Sicurezza è tutto ciò che ci protegge, dalla prevenzione dei disastri naturali ai conflitti armati, passando per tutte le scale intermedie di disordini, come sommosse, movimenti migratori incontrollati, controllo di ogni tipo di traffico, ecc. Strategia si riferisce, invece, non solo ad un lasso di tempo ma anche a con chi si coopera e attraverso quali contributi. Riassunto di questa riflessione è che chi non sarà in grado di controllare lo spazio non sarà in grado di controllare il proprio futuro, con tutte le conseguenze che tale circostanza può comportare.

Il tema può essere suddiviso tra ciò che avviene dall’alto verso il basso (la Terra) e dal basso verso l’alto (lo spazio) e tra ciò che avviene, o potrebbe accadere in futuro, nello spazio stesso. L’ordine citato si riferisce, per convenienza, alla situazione attuale, ma in nessun modo si stabilisce che sia il più importante e che, nel breve periodo, misurato nell’era geologica, sarà l’ultimo menzionato.

La sicurezza pone le sue basi sull’osservazione, la conoscenza, la prevenzione e l’intervento, nel caso quest’ultimo fosse necessario; per questo nulla come occhi e orecchie che abbiano una portata globale permettono un controllo continuo 24 ore su 24. La questione verte sulla possibilità di sapere come si sta modificando l’ambiente terrestre, al fine di ottenere un vantaggio competitivo nello sfruttamento delle risorse, nel controllo delle rotte di traffici sospetti, nella guida di sistemi armati verso l’obiettivo.

Senza arrivare a questi estremi, è evidente che l’occultamento di certi dati può risultare assai dannoso per chi ne soffre, per esempio nel caso di un’allerta tsunami o l’arrivo di un uragano. Le informazioni devono arrivare al destinatario in breve tempo e senza distorsioni, spurie o provocate, il che richiede nella maggioranza dei casi una rete di comunicazione satellitare. E’ quindi essenziale appartenere ad un “club” che possiede tali mezzi satellitari di comunicazione, meteorologici, di navigazione e posizionamento, di osservazione, sia a titolo esclusivo sia in collaborazione con altri paesi.

Menzionando la parola “satellite” (artificiale) si apre il discorso legato ai veicoli lanciati in orbita. Va precisato che questi razzi sono vecchi di cent’anni e non ne è stata migliorata la funzionalità, nonostante la loro tecnologia (vedi Figura 1) per questo numerose nazioni possono produrli con minore o maggiore potenzialità.

Altra cosa è sviluppare carichi utili da trasportare con questi veicoli (come il primo Sputnik), ed è difficile poi avere la tecnologia sufficiente che permetta il rientro controllato di un artefatto. Pochi paesi la possiedono e la Spagna è socia di alcuni di essi.

Figura 1

Ricordiamo inoltre che ogni giorno passa sopra le nostre teste un oggetto delle dimensioni di uno stadio di calcio, la Stazione Internazionale Spaziale (vedi figura 2) le cui finalità sono esclusivamente pacifiche: tuttavia intimorisce ciò che altri paesi potrebbero fare godendo di infrastrutture simili.

Figura 2

L’investigazione dello spazio dalla Terra o dai satelliti (che sulla scala cosmologica è come se si trovassero sulla Terra) ci permette di sapere che l’universo è molto più grande e complesso di quello che sospettiamo, che ci sono migliaia di pianeti nelle stelle vicine (quindi per il principio isotopico ci saranno anche nelle altre) e che l’acqua è uno degli elementi più comuni, non solo nel sistema solare (vedi figura 3) ma nello spazio stesso. Da qui dedurre che debba esserci vita extraterrestre è solo un passo logico, nonostante tardiamo a confermarlo.

Figura 3

L’importante non è sapere se prima o poi entreremo in contatto con altre forme di vita intelligente o meno, ma rompere il paradigma secondo cui siamo soli nell’universo. La questione ha connotazioni filosofiche e comporta un cambiamento a lungo termine, che supera di gran lunga la maggior parte delle sfide che dobbiamo affrontare nel presente. Al riguardo, poniamo una semplice questione: dobbiamo continuare a radiotrasmettere come facciamo ora, dimostrando all’universo che non esiste un modo più discreto di comunicare?.

Al di là della questione della vita (extraterrestre), per quanto importante essa sia, sono i cosiddetti “Oggetti Celesti” (NEO in inglese) che possono impattare con la Terra, e produrre conseguenze e danni assai gravi, tra cui l’estinzione della razza umana stessa. La figura 4 mostra la probabilità che un oggetto impatti sulla Terra, in funzione della sua capacità distruttiva (in mega tonnellate equivalenti di TNT), che dipende dalle sue dimensioni e dalla sua composizione chimica. Ogni giorno cadono sulla Terra tonnellate di materia, soprattutto acqua, nell’atmosfera terrestre, e solo gli oggetti più grandi e più densi toccano la superficie. Il recente meteorite in Siberia è uno di questi. Possiamo facilmente immaginare cosa potrebbe accadere se un oggetto di tali dimensioni cadesse in una zona densamente popolata.

Figura 4

E’ possibile deviare dalla loro orbita questi oggetti, sebbene questi viaggino ad una velocità di 25 Km al secondo, se intercettati con un sufficiente anticipo (il che richiede un vasto sistema di osservazione, perfettamente coordinato, di questi oggetti). Qui si apre, tuttavia, la seconda questione: se qualcuno è in grado deviare un oggetto celeste, può far impedire che questo impatti con la Terra, ma anche il contrario. Siamo di fronte ad una nuova minaccia criminale?

Analizzando ciò che è accaduto durante la Rivoluzione Industriale del XIX secolo, quando all’interno delle città si svilupparono grandi centri industriali, o crebbero attorno ad esse, quando il problema era legato al trasporto su larga scala di individui, deduciamo che anche oggi, una volta risolto il problema del trasporto spaziale, potremmo cominciare a ubicare impianti di produzione nello spazio, a cominciare dagli impianti legati allo sfruttamento dell’energia solare, che potranno lavorare come se non arrivasse mai la notte (vedi figura 5). Quello che è certo è che trasmettere giga-watt di energia attraverso micro -onde indirizzate verso la superficie terrestre danneggerà l’atmosfera, ma sicuramente in modo meno dannoso di quanto non accada bruciando carbone o derivati del petrolio, come succede oggi.

Figura 5

Si potrà inoltre risolvere il problema legato all’acqua, utilizzando blocchi di ghiaccio di forme controllate (le comete e gli anelli di Saturno sono fra questi), di modo da poter aumentare la proporzione di acqua nell’atmosfera. La stessa acqua servirebbe da combustibile e, a differenza di quanto accade con i missili, il suo rientro sulla Terra non sarebbe dannoso per l’atmosfera terrestre.

Dobbiamo tener presente che la Terra non è un pianeta isolato, data la presenza di un satellite relativamente grande vicino a noi. Pertanto dobbiamo considerare il concetto Terra-Luna, così come sviluppato dall’Agenzia Spaziale alla fine del secolo scorso, attraverso la sua Commissione Politica a lungo termine. In questa sfera di circa 3 milioni di diametro, oltre ai corpi celesti maggiori, esistono milioni di altri corpi celesti naturali, oltre ai già citati NEO’s, tutti suscettibili di poter essere utilizzati a tempo debito. Solo sulla superficie lunare sono presenti miglia di volte in più di particelle di trizio, l’isotopo di idrogeno fondamentale per la fusione nucleare, rispetto a quante ce ne siano sulla Terra.

Potremmo definire tutto questo fantascienza, però basta ricordare che sono passati circa duecento anni dalla scoperta dell’elettricità, un tempo minimo se comparato con l’esistenza della razza umana. Nel caso spagnolo, il ritardo rispetto ai progressi raggiunti da altre nazioni a partire dal secolo XIX ci ha portati ad uno stato di prostrazione dal quale non siamo ancora usciti.
A dimostrazione di ciò basta leggere il giornale “El Paìs” del 19 febbraio 1985, dove un gruppo di esperti e di alti funzionari raccomandavano al governo dell’epoca di non dotarsi di satelliti per la comunicazione. Questo meno di 30 anni fa!

Figura 6 e 7

Riassumendo, l’attività spaziale è qualcosa di imprescindibile non solo per la nostra sicurezza, ma anche per la nostra sopravvivenza. Nel breve periodo, possiamo sostenere che solo le democrazie hanno sicurezza sociale, appoggio governativo alle Belle Arti e programmi speciali. Tuttavia questo non è sufficiente. Né lo sarà la creazione di posti di lavoro altamente qualificati, perché lo spazio è come il sale e il pepe negli alimenti, un grande valore aggiunto, ma scarso quantitativamente.

Altra cosa ancora sono le applicazioni derivate dallo spazio, come le telecomunicazioni, che non potremmo certo definire un’impresa stile Apple. Essenzialmente, non avere nulla, o molto poco, di ciò che è offerto dallo spazio, è un errore da un punto di vista strategico, che condanna a non poter decidere del proprio futuro.

A soli 10 euro a persona all’anno, tra investimenti privati e pubblici, la Spagna avrà un piano spaziale più che dignitoso, con un importo non certo straordinario, considerando che oggi, nonostante la crisi, la media europea è quasi il doppio, senza menzionare quanto investono le altre potenze industriali.

Figura 8

Per questo riveste una grande importanza strategica, per la Spagna, che questa offra ai suoi soci (europei e non) alcune capacità specifiche, attraverso l’applicazione immediata di strumenti di screening, mediante una cooperazione forte all’interno degli organismi internazionali, come EUMESAT, L’Agenzia Spazialel Europea, Galileo, e operatori come Hispasat e Hisdesat.

Il contributo per la sopravvivenza della specie, che è ancorato ad un punto minuscolo, ma bellissimo, dello spazio, merita certamente la spesa di pochi euro a persona, non tanto perché si tratta di pochi euro, quanto perché, parafrasando Churchill, questo poco potrà fare molto, come non mai, per questo paese.  L’arrivo della sonda Rosetta sulla cometa Gerasimov, previsto per l’anno prossimo, grazie ad un importantissimo contributo tecnologico spagnolo, è un magnifico esempio di come la Spagna è parte dello sviluppo della conoscenza, e la conoscenza è la base e il sostegno per la sicurezza.

Álvaro Azcárraga Arana è ingegnere aeronautico membro della Commissione Permanente di Ricerca Spaziale del CESEDEN

Glass sponges take advantage of retreating Antarctic ice shelves

Bremerhaven, 11th July 2013. The breakup and collapse of the Larsen A ice shelf in the western Weddell Sea in 1995 has resulted in fundamental changes to life on the sea bed in less than two decades.  As reported by biologists from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research in the cover story of the current issue of the scientific journal Current Biology, Antarctic glass sponges have been the prime beneficiaries of the disappearance of the ice shelf. To the surprise of the scientists, the density of these archaic filter-feeders has increased threefold between 2007 and 2011 despite only low plankton food supply and water temperatures of minus 2 degrees Celsius.  The sponges had also grown remarkably quickly and had completely supplanted competitors for food.  The results show that communities at the bottom of the western Weddell Sea react considerably more quickly to climate-related changes than previously thought. 

Glass sponges (Hexactinellida), an archaic group of animals at the basis of the animal kingdom, dominate the shallow seafloor in the Antarctic.  Many biologists believed that glass sponges grew so slowly that two-metre behemoths would have to be around 10,000 years or older.  These assumptions have now been challenged in a new study led by scientists from the Alfred Wegener Institute (AWI) and published in the current issue of the scientific journal Current Biology. 

During a Polarstern expedition to the poorly accessible region of the former Larsen A ice shelf, AWI biologists Laura Fillinger and Claudio Richter, together with colleagues from the University of Gothenburg and the Senkenberg Research Institute and Natural History Museum; succeeded in demonstrating that glass sponges can grow rapidly within a short period of time.  “We were surprised by what we saw on our video screens in 2011 when we lowered our remotely operated vehicle onto the sea bed at a depth of around 140 metres.  In an area, which had revealed large numbers of ascidians and only occasional glass sponges during an earlier expedition with the ice-breaking research vessel ‘Polarstern’ in 2007, four years later we found no ascidians at all.  These pioneer species had completely disappeared, replaced by three times the number of glass sponges, including several juvenile individuals”, reports Laura Fillinger, lead author of the study. 

Until this time scientists had assumed that communities on the Antarctic sea bed only change very slowly because of the very low temperature (minus two degrees Celsius) and patchy supply of food in pack-ice covered waters.  “We now know that glass sponges may undergo boom-and-bust cycles, allowing them to quickly colonize new habitats in a short period of time”, says project leader Prof. Dr. Claudio Richter.

“To the organisms living on the sea bed, the disappearance of the hundred-metre-thick Larsen A ice shelf must have been like the heavens opening up above them”, he adds.  Where cold, darkness and food shortages had previously reigned, sunlight now allows plankton growth in surface waters and, hence, a rain of food comes down to the sea bed.  

 Glass sponges feed on the smallest plankton, which they filter from the water.  The animals grow to a size of up to two metres, and their vase-like bodies provide perfect hiding, spawning and shelter opportunities for fish, invertebrates and many other sea dwellers.  “Like corals, sponges create their own habitats.  To an extent they are like cities on the sea bed. There is something going on wherever they grow, and this attracts other sea dwellers to them”, says Claudio Richter. 

New spaces are being created for such underwater worlds wherever the ice shelves on the Antarctic Peninsula are retreating or breaking up.  However, scientists cannot yet definitively say whether this means that glass sponges will be one of the beneficiaries of climate change.  Laura Fillinger: “There are still too many unknowns to make predictions.  One example is the question of the influence of competitors: currently we are witnessing a fierce competition for space on the sea bed.  Another concerns predators: in our dive in 2011 we hardly saw any of the snails and starfish, which feed on glass sponges.  However, it is possible that these voracious predators will follow suit and wreak havoc.” 

Huge iceberg breaks away from the Pine Island glacier in the Antarctic

Bremerhaven, 9 July 2013. Yesterday (8 July 2013) a huge area of the ice shelf broke away from the Pine Island glacier, the longest and fastest flowing glacier in the Antarctic, and is now floating in the Amundsen Sea in the form of a very large iceberg. Scientists of the Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association have been following this natural spectacle via the earth observation satellites TerraSAR-X from the German Space Agency (DLR) and have documented it in many individual images. The data is intended to help solve the physical puzzle of this “calving“.

Scientists from the American space agency NASA discovered the first crack in the glacier tongue on 14 October 2011 when flying over the area. At that time it was some 24 kilometres long and 50 metres wide. ”As a result of these cracks, one giant iceberg broke away from the glacier tongue. It measures 720 square kilometres and is therefore almost as large as the city of Hamburg“, reports Prof. Angelika Humbert, ice researcher at the Alfred Wegener Institute. 

The glaciologist and her team used the high resolution radar images of the DLR earth observation satellite TerraSAR-X to observe the progress of the two cracks and to better understand the physical processes behind the glacier movements. The researchers were thus able to measure the widths of the gaps and calculate the flow speed of the ice. ”Above the large crack, the glacier last flowed at a speed of twelve metres per day“, reports Humbert’s colleague Dr. Dana Floricioiu from DLR. And Nina Wilkens, PhD graduate in Prof. Humbert’s team, adds: “Using the images we have been able to follow how the larger crack on the Pine Island glacier extended initially to a length of 28 kilometres. Shortly before the “birth” of the iceberg, the gap then widened bit by bit so that it measured around 540 metres at its widest point.“

The scientists incorporate these and other TerraSAR-X satellite data in computer simulations using which they are able to model the break and flow mechanisms of the ice masses. “Glaciers are constantly in motion. They have their very own flow dynamics. Their ice is exposed to permanent tensions and the calving of icebergs is still largely unresearched “, explains ice modeller Angelika Humbert. 

The scientist and her team then compare their simulation results with current satellite data such as from TerraSAR-X. If the model agrees with reality, the scientists can conclude, for example, the gliding property of the ground beneath the glacier ice and how the ice flow could behave in the event of further global warming. 

Are ice breaks caused by climate change? Angelika Humbert does not so far see any direct connection: “The creation of cracks in the shelf ice and the development of new icebergs are natural processes“, says the glaciologist. However, the Pine Island glacier, which flows from the Hudson mountains to the Amundsen Sea, was the fastest flowing glacier in the Western Antarctic with a flow speed of around 4 kilometres per year. This speed is less caused by the rising air temperatures, however, and is more attributable to the fact that the wind directions in the Amundsen Sea have altered. ”The wind now brings warm sea water beneath the shelf ice. Over time, this process means that the shelf ice melts from below, primarily at the so-called grounding line, the critical transition to the land ice“, says the scientist. 

For the Western Antarctic ice shelf, an even faster flow of the Pine Island glacier would presumably have serious consequences. “The Western Antarctic land ice is on land which is deeper than sea level. Its “bed” tends towards the land. The danger therefore exists that these large ice masses will become unstable and will start to slide“, says Angelika Humbert. If the entire West Antarctic ice shield were to flow into the Ocean, this would lead to a global rise in sea level of around 3.3 metres. 

Info box: Shelf ice 

The shelf ice, which is 200 to 1200 metres, thick is created by glaciers sliding into the sea. It is therefore an extension of the Antarctic land ice which thins at the edges and floats on the sea. The ice shelf itself rests on the Antarctic continent, reaching a thickness of up to four kilometres and is largely frozen to the rock bottom. A special feature of the Western Antarctic is that large areas of land are below sea level. (AWI press release, july 9,2013)

Miscellanea Artico : News feature: 2013-197

June 10, 2013 Is a Sleeping Climate Giant Stirring in the Arctic? Flying low and slow above the wild, pristine terrain of Alaska's North Slope in a specially instrumented NASA plane, research scientist Charles Miller of NASA's Jet Propulsion Laboratory, Pasadena, Calif., surveys the endless whiteness of tundra and frozen permafrost below. On the horizon, a long, dark line appears. The plane draws nearer, and the mysterious object reveals itself to be a massive herd of migrating caribou, stretching for miles. It's a sight Miller won't soon forget. "Seeing those car  ibou marching single-file across the tundra puts what we're doing here in the Arctic into perspective," said Miller, principal investigator of the Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE), a five-year NASA-led field campaign studying how climate change is affecting the Arctic's carbon cycle. "The Arctic is critical to understanding global climate," he said. "Climate change is already happening in the Arctic, faster than its ecosystems can adapt. Looking at the Arctic is like looking at the canary in the coal mine for the entire Earth system." Aboard the NASA C-23 Sherpa aircraft from NASA's Wallops Flight Facility, Wallops Island, Va., Miller, CARVE Project Manager Steve Dinardo of JPL and the CARVE science team are probing deep into the frozen lands above the Arctic Circle. The team is measuring emissions of the greenhouse gases carbon dioxide and methane from thawing permafrost -- signals that may hold a key to Earth's climate future. What Lies Beneath Permafrost (perennially frozen) soils underlie much of the Arctic. Each summer, the top layers of these soils thaw. The thawed layer varies in depth from about 4 inches (10 centimeters) in the coldest tundra regions to several yards, or meters, in the southern boreal forests. This active soil layer at the surface provides the precarious foothold on which Arctic vegetation survives. The Arctic's extremely cold, wet conditions prevent dead plants and animals from decomposing, so each year another layer gets added to the reservoirs of organic carbon sequestered just beneath the topsoil. Over hundreds of millennia, Arctic permafrost soils have accumulated vast stores of organic carbon - an estimated 1,400 to 1,850 petagrams of it (a petagram is 2.2 trillion pounds, or 1 billion metric tons). That's about half of all the estimated organic carbon stored in Earth's soils. In comparison, about 350 petagrams of carbon have been emitted from all fossil-fuel combustion and human activities since 1850. Most of this carbon is located in thaw-vulnerable topsoils within 10 feet (3 meters) of the surface. But, as scientists are learning, permafrost - and its stored carbon - may not be as permanent as its name implies. And that has them concerned. "Permafrost soils are warming even faster than Arctic air temperatures - as much as 2.7 to 4.5 degrees Fahrenheit (1.5 to 2.5 degrees Celsius) in just the past 30 years," Miller said. "As heat from Earth's surface penetrates into permafrost, it threatens to mobilize these organic carbon reservoirs and release them into the atmosphere as carbon dioxide and methane, upsetting the Arctic's carbon balance and greatly exacerbating global warming." Current climate models do not adequately account for the impact of climate change on permafrost and how its degradation may affect regional and global climate. Scientists want to know how much permafrost carbon may be vulnerable to release as Earth's climate warms, and how fast it may be released. CARVing Out a Better Understanding of Arctic Carbon Enter CARVE. Now in its third year, this NASA Earth Ventures program investigation is expanding our understanding of how the Arctic's water and carbon cycles are linked to climate, as well as what effects fires and thawing permafrost are having on Arctic carbon emissions. CARVE is testing hypotheses that Arctic carbon reservoirs are vulnerable to climate warming, while delivering the first direct measurements and detailed regional maps of Arctic carbon dioxide and methane sources and demonstrating new remote sensing and modeling capabilities. About two dozen scientists from 12 institutions are participating. "The Arctic is warming dramatically - two to three times faster than mid-latitude regions - yet we lack sustained observations and accurate climate models to know with confidence how the balance of carbon among living things will respond to climate change and related phenomena in the 21st century," said Miller. "Changes in climate may trigger transformations that are simply not reversible within our lifetimes, potentially causing rapid changes in the Earth system that will require adaptations by people and ecosystems." The CARVE team flew test flights in 2011 and science flights in 2012. This April and May, they completed the first two of seven planned monthly campaigns in 2013, and they are currently flying their June campaign. Each two-week flight campaign across the Alaskan Arctic is designed to capture seasonal variations in the Arctic carbon cycle: spring thaw in April/May, the peak of the summer growing season in June/July, and the annual fall refreeze and first snow in September/October. From a base in Fairbanks, Alaska, the C-23 flies up to eight hours a day to sites on Alaska's North Slope, interior and Yukon River Valley over tundra, permafrost, boreal forests, peatlands and wetlands. The C-23 won't win any beauty contests - its pilots refer to it as "a UPS truck with a bad nose job." Inside, it's extremely noisy - the pilots and crew wear noise-cancelling headphones to communicate. "When you take the headphones off, it's like being at a NASCAR race," Miller quipped. But what the C-23 lacks in beauty and quiet, it makes up for in reliability and its ability to fly "down in the mud," so to speak. Most of the time, it flies about 500 feet (152 meters) above ground level, with periodic ascents to higher altitudes to collect background data. Most airborne missions measuring atmospheric carbon dioxide and methane do not fly as low. "CARVE shows you need to fly very close to the surface in the Arctic to capture the interesting exchanges of carbon taking place between Earth's surface and atmosphere," Miller said. Onboard the plane, sophisticated instruments "sniff" the atmosphere for greenhouse gases. They include a very sensitive spectrometer that analyzes sunlight reflected from Earth's surface to measure atmospheric carbon dioxide, methane and carbon monoxide. This instrument is an airborne simulator for NASA's Orbiting Carbon Observatory-2 (OCO-2) mission to be launched in 2014. Other instruments analyze air samples from outside the plane for the same chemicals. Aircraft navigation data and basic weather data are also collected. Initial data are delivered to scientists within 12 hours. Air samples are shipped to the University of Colorado's Institute for Arctic and Alpine Research Stable Isotope Laboratory and Radiocarbon Laboratory in Boulder for analyses to determine the carbon's sources and whether it came from thawing permafrost. Much of CARVE's science will come from flying at least three years, Miller says. "We are showing the power of using dependable, low-cost prop planes to make frequent, repeat measurements over time to look for changes from month to month and year to year." Ground observations complement the aircraft data and are used to calibrate and validate them. The ground sites serve as anchor points for CARVE's flight tracks. Ground data include air samples from tall towers and measurements of soil moisture and temperature to determine whether soil is frozen, thawed or flooded. A Tale of Two Greenhouse Gases It's important to accurately characterize the soils and state of the land surfaces. There's a strong correlation between soil characteristics and release of carbon dioxide and methane. Historically, the cold, wet soils of Arctic ecosystems have stored more carbon than they have released. If climate change causes the Arctic to get warmer and drier, scientists expect most of the carbon to be released as carbon dioxide. If it gets warmer and wetter, most will be in the form of methane. The distinction is critical. Molecule per molecule, methane is 22 times more potent as a greenhouse gas than carbon dioxide on a 100-year timescale, and 105 times more potent on a 20-year timescale. If just one percent of the permafrost carbon released over a short time period is methane, it will have the same greenhouse impact as the 99 percent that is released as carbon dioxide. Characterizing this methane to carbon dioxide ratio is a major CARVE objective. There are other correlations between Arctic soil characteristics and the release of carbon dioxide and methane. Variations in the timing of spring thaw and the length of the growing season have a major impact on vegetation productivity and whether high northern latitude regions generate or store carbon. CARVE is also studying wildfire impacts on the Arctic's carbon cycle. Fires in boreal forests or tundra accelerate the thawing of permafrost and carbon release. Detailed fire observation records since 1942 show the average annual number of Alaska wildfires has increased, and fires with burn areas larger than 100,000 acres are occurring more frequently, trends scientists expect to accelerate in a warming Arctic. CARVE's simultaneous measurements of greenhouse gases will help quantify how much carbon is released to the atmosphere from fires in Alaska - a crucial and uncertain element of its carbon budget. Early Results The CARVE science team is busy analyzing data from its first full year of science flights. What they're finding, Miller said, is both amazing and potentially troubling. "Some of the methane and carbon dioxide concentrations we've measured have been large, and we're seeing very different patterns from what models suggest," Miller said. "We saw large, regional-scale episodic bursts of higher-than-normal carbon dioxide and methane in interior Alaska and across the North Slope during the spring thaw, and they lasted until after the fall refreeze. To cite another example, in July 2012 we saw methane levels over swamps in the Innoko Wilderness that were 650 parts per billion higher than normal background levels. That's similar to what you might find in a large city." Ultimately, the scientists hope their observations will indicate whether an irreversible permafrost tipping point may be near at hand. While scientists don't yet believe the Arctic has reached that tipping point, no one knows for sure. "We hope CARVE may be able to find that 'smoking gun,' if one exists," Miller said. Other institutions participating in CARVE include City College of New York; the joint University of Colorado/National Oceanic and Atmospheric Administration's Cooperative Institute for Research in Environmental Sciences, Boulder, Colo.; San Diego State University; University of California, Irvine; California Institute of Technology, Pasadena; Harvard University, Cambridge, Mass.; University of California, Berkeley; Lawrence Berkeley National Laboratory, Berkeley, Calif.; University of California, Santa Barbara; NOAA's Earth System Research Laboratory, Boulder, Colo.; and University of Melbourne, Victoria, Australia. NASA NEWS -

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Russia: Evacuation of Polar researches to start this week

 The Russian Government pays 65 million rubles to bring the crew of the floating research station “North Pole-40” safely back to land.

By

Trude Pettersen

May 27, 2013

Russia’s Prime Minister Dmitry Medvedev has approved the plans for evacuation of 16 persons and large amounts of materials from the floating research station “North Pole-40”, drifting close to the North Pole. As BarentsObserverreported, the ice floe carrying the station has started to break up and the scientists and equipment need to evacuated before long.

The nuclear-powered icebreaker “Yamal” is now preparing to leave for the Arctic Ocean on a rescue mission. The vessel is planned to leave Murmansk by the end of this week and will reach the station approximately two weeks later. The rescue mission is estimated to cost 65 million rubles (app €1.6 million).

The ice floe has now broken up in pieces that are 100 times 150 meters large, Head of the Federal Service for Hydrometeorology and Environmental Monitoring Aleksander Frolov says to Rossiyskaya Gazeta. The piece the research station is located on is about 2.5 meters thick. The air temperature in the area is -10 and rising.

The crew cannot be rescued by plane or helicopter, Frolov says. Because of ice ridging on the floe, it is not possible to build an airstrip for any plane, and the floe has drifted out of reach for helicopters.

The scientific station “North Pole-40” will continue its work in the Arctic even after it has been removed from the ice floe. An abandoned Polar station in Mys Baranova on Severnaya Zemlya is now being prepared to house the researchers and their equipment.

Russia has had floating research stations in the Arctic since 1937, when the first scientific drifting ice station in the world – “North Pole-1”, was established. From 1954 Soviet "North Pole" stations worked continuously, with one to three such stations operating simultaneously every year. In the post-Soviet era, Russian exploration of the Arctic by drifting ice stations was suspended for twelve years, and was resumed in 2003. (Barents Observer)

Seal of quality on the anniversary

(a cura di Alberto Marenga)

Osservazioni satellitari per il buco dell'Ozono

Satellites show that the recent ozone hole over Antarctica was the smallest seen in the past decade. Long-term observations also reveal that Earth’s ozone has been strengthening following international agreements to protect this vital layer of the atmosphere.

According to the ozone sensor on Europe’s MetOp weather satellite, the hole over Antarctica in 2012 was the smallest in the last 10 years.

The instrument continues the long-term monitoring of atmospheric ozone started by its predecessors on the ERS-2 and Envisat satellites.

Since the beginning of the 1980s, an ozone hole has developed over Antarctica during the southern spring – September to November – resulting in a decrease in ozone concentration of up to 70%.

Ozone depletion is more extreme in Antarctica than at the North Pole because high wind speeds cause a fast-rotating vortex of cold air, leading to extremely low temperatures.

Under these conditions, human-made chlorofluorocarbons – CFCs – have a stronger effect on the ozone, depleting it and creating the infamous hole.

Over the Arctic, the effect is far less pronounced because the northern hemisphere’s irregular landmasses and mountains normally prevent the build-up of strong circumpolar winds.

Reduced ozone over the southern hemisphere means that people living there are more exposed to cancer-causing ultraviolet radiation.

International agreements on protecting the ozone layer – particularly the Montreal Protocol – have stopped the increase of CFC concentrations, and a drastic fall has been observed since the mid-1990s.

However, the long lifetimes of CFCs in the atmosphere mean it may take until the middle of this century for the stratosphere’s chlorine content to go back to values like those of the 1960s.

The evolution of the ozone layer is affected by the interplay between atmospheric chemistry and dynamics like wind and temperature.

If weather and atmospheric conditions show unusual behaviour, it can result in extreme ozone conditions – such as the record low observed in spring 2011 in the Arctic – or last year’s unusually small Antarctic ozone 

Ancient microbes found in Antarctic lake

Nearly 65 feet beneath the icy surface of a remote Antarctic lake, scientists from NASA, the Desert Research Institute (DRI) in Reno, Nev., the University of Illinois at Chicago, and nine other institutions, have uncovered a community of bacteria existing in one of Earth's darkest, saltiest and coldest habitats.

Lake Vida, the largest of several unique lakes found in the McMurdo Dry Valleys, contains no oxygen, is mostly frozen and possesses the highest nitrous oxide levels of any natural water body on Earth. A briny liquid, which is approximately six times saltier than seawater, percolates throughout the icy environment where the average temperature is minus 8 degrees Fahrenheit. The international team of scientists published their findings online Nov. 26, in the Proceedings of the National Academy of Sciences Early Edition.

"This study provides a window into one of the most unique ecosystems on Earth," said Alison Murray, a molecular microbial ecologist and polar researcher at the DRI and the report's lead author. "Our knowledge of geochemical and microbial processes in lightless icy environments, especially at subzero temperatures, has been mostly unknown up until now. This work expands our understanding of the types of life that can survive in these isolated, cryoecosystems and how different strategies may be used to exist in such challenging environments."

Despite the very cold, dark and isolated nature of the habitat, the report finds the brine harbors a surprisingly diverse and abundant variety of bacteria that survive without a current source of energy from the sun. Previous studies of Lake Vida dating back to 1996 indicate the brine and its inhabitants have been isolated from outside influences for more than 3,000 years.

"This system is probably the best analog we have for possible ecosystems in the subsurface waters of Saturn's moon Enceladus and Jupiter's moon Europa," said Chris McKay, a senior scientist and co-author of the paper at NASA's Ames Research Center, Moffett Field, Calif.

Murray and her co-authors and collaborators, including Peter Doran, the project's principal investigator at the University of Illinois at Chicago, developed stringent protocols and specialized equipment for their 2005 and 2010 field campaigns to sample from the lake brine while avoiding contaminating the pristine ecosystem.

"The microbial ecosystem discovered at Lake Vida expands our knowledge of environmental limits for life and helps define new niches of habitability," said Adrian Ponce, co-author from NASA's Jet Propulsion Laboratory, Pasadena, Calif., who enumerated viable bacterial spore populations extracted from Lake Vida.

To sample unique environments such as this, researchers must work under secure, sterile tents on the lake's surface. The tents kept the site and equipment clean as researchers drilled ice cores, collected samples of the salty brine residing in the lake ice and assessed the chemical qualities of the water and its potential for harboring and sustaining life.

Geochemical analyses suggest chemical reactions between the brine and the underlying iron-rich sediments generate nitrous oxide and molecular hydrogen. The latter, in part, may provide the energy needed to support the brine's diverse microbial life.

Additional research is under way to analyze the abiotic, chemical interactions between the Lake Vida brine and its sediment, in addition to investigating the microbial community by using different genome sequencing approaches. The results could help explain the potential for life in other salty, cryogenic environments beyond Earth, such as purported subsurface aquifers on Mars.

(NASA news, nov.30,2012)

Amplified Grenhouse Effect Schifta North's Growing Seasoms

Amplified Greenhouse Effect Shifts North's Growing Seasons

March 10, 2013: Vegetation growth at Earth's northern latitudes increasingly resembles lusher latitudes to the south, according to a NASA-funded study based on a 30-year record of ground-based and satellite data sets.
In a paper published Sunday, March 10, in the journal Nature Climate Change, an international team of university and NASA scientists examined the relationship between changes in surface temperature and vegetation growth from 45 degrees north latitude to the Arctic Ocean. Results show temperature and vegetation growth at northern latitudes now resemble those found 4 degrees to 6 degrees of latitude farther south as recently as 1982.
"Higher northern latitudes are getting warmer, Arctic sea ice and the duration of snow cover are diminishing, the growing season is getting longer and plants are growing more," said Ranga Myneni of Boston University's Department of Earth and Environment. "In the north's Arctic and boreal areas, the characteristics of the seasons are changing, leading to great disruptions for plants and related ecosystems."

Of the 10 million square miles (26 million square kilometers) of northern vegetated lands, 34 to 41 percent showed increases in plant growth (green and blue), 3 to 5 percent showed decreases in plant growth (orange and red), and 51 to 62 percent showed no changes (yellow) over the past 30 years. Satellite data in this visualization are from AVHRR and MODIS. Credit: NASA's Goddard Space Flight Center Scientific Visualization Studio Myneni and colleagues used satellite data to quantify vegetation changes at different latitudes from 1982 to 2011. Data used in this study came from NOAA's Advanced Very High Resolution Radiometers (AVHRR) onboard a series of polar-orbiting satellites and NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) instruments on the Terra and Aqua satellites.
As a result of enhanced warming and a longer growing season, large patches of vigorously productive vegetation now span a third of the northern landscape, or more than 3.5 million square miles (9 million square kilometers). That is an area about equal to the contiguous United States. This landscape resembles what was found 250 to 430 miles (400 to 700 kilometers) to the south in 1982.

"It's like Winnipeg, Manitoba, moving to Minneapolis-Saint Paul in only 30 years," said co-author Compton Tucker of NASA's Goddard Space Flight Center in Greenbelt, Md.

The Arctic's greenness is visible on the ground as an increasing abundance of tall shrubs and trees in locations all over the circumpolar Arctic. Greening in the adjacent boreal areas is more pronounced in Eurasia than in North America.
An amplified greenhouse effect is driving the changes, according to Myneni. Increased concentrations of heat-trapping gasses, such as water vapor, carbon dioxide and methane, cause Earth's surface, ocean and lower atmosphere to warm. Warming reduces the extent of polar sea ice and snow cover, and, in turn, the darker ocean and land surfaces absorb more solar energy, thus further heating the air above them.
"This sets in motion a cycle of positive reinforcement between warming and loss of sea ice and snow cover, which we call the amplified greenhouse effect," Myneni said. "The greenhouse effect could be further amplified in the future as soils in the north thaw, releasing potentially significant amounts of carbon dioxide and methane."

To find out what is in store for future decades, the team analyzed 17 climate models. These models show that increased temperatures in Arctic and boreal regions would be the equivalent of a 20-degree latitude shift by the end of this century relative to a period of comparison from 1951-1980. However, researchers note that plant growth in the north may not continue on its current trajectory. The ramifications of an amplified greenhouse effect, such as frequent forest fires, outbreak of pest infestations and summertime droughts, may slow plant growth. Also, warmer temperatures alone in the boreal zone do not guarantee more plant growth, which also depends on the availability of water and sunlight.
"Satellite data identify areas in the boreal zone that are warmer and dryer and other areas that are warmer and wetter," said co-author Ramakrishna Nemani of NASA's Ames Research Center in Moffett Field, Calif. "Only the warmer and wetter areas support more growth."
"We found more plant growth in the boreal zone from 1982 to 1992 than from 1992 to 2011, because water limitations were encountered in the later two decades of our study," said co-author Sangram Ganguly of the Bay Area Environmental Research Institute and NASA Ames.
Data, results and computer codes from this study will be made available on NASA Earth Exchange (NEX), a collaborative supercomputing facility at Ames Research Center, Moffett Field, Calif. NEX is designed to bring scientists together with data, models and computing resources to accelerate research and innovation and provide transparency. (NASA Science march 10,2013)

Antarctic and Artic Insects Use Different Genetic Mechanisms to Cope With LAck of Water

Genomic techniques facilitate discovery that gene expression causes disparity

March 11, 2013

Although they live in similarly extreme ecosystems at opposite ends of the world, Antarctic insects appear to employ entirely different methods at the genetic level to cope with extremely dry conditions than their counterparts that live north of the Arctic Circle, according to National Science Foundation- (NSF) funded researchers.

Writing in the Proceedings of the National Academy of Sciences, the researchers concluded, "Polar arthropods have developed distinct... mechanisms to cope with similar desiccating conditions."

The researchers noted that aside from the significance of the specific discovery about the genetics of how creatures cope in polar environments, the new finding is important because it shows how relatively new and developing scientific techniques, including genomics, are opening new scientific vistas in the Polar Regions, which were once thought to be relatively uniform and, relatively speaking, scientifically sterile environments.

"It's great to have an Antarctic animal that has entered the genomic era," said David Denlinger, a distinguished professor of entomology at Ohio State University and a co-author of the paper. "This paper, which analyzed the expression of thousands of genes in response to the desiccating environment of Antarctica, is just one example of the power that the genomic revolution offers for advancing polar science. "

The collaborative research--which included contributions from scientists at Ohio State University, the Centre National de la Recherche Scientifique (National Center for Scientific Research) in France, Catholic University of Louvain in Belgium, Stanford University, and Miami University in Ohio--was supported in part by the Division of Polar Programs in NSF's Geosciences Directorate.

Polar Programs manages the U.S. Antarctic Program, through which it coordinates all U.S. research on the southernmost continent and aboard ships in the Southern Ocean as well as providing the necessary logistical support.

The finding also adds to the developing picture of the Polar Regions as having similarities and yet subtle and perhaps very important differences, previously undetected by science. NSF-funded scientists late last year, for example, published researchindicating that differing contributions of freshwater from glaciers and streams to the Arctic and Southern oceans may be responsible for the fact that the majority of microbial communities that thrive near the surface of the Polar oceans share few common members.

Although Antarctica's surrounding oceans and coastal margins are home to a variety of large creatures such as seals, penguins and whales, insect life is rare, except on the Antarctic Peninsula.

There, the Antarctic midge, Belgica antarctica, occupies its unique ecological niche.

The research team that produced the new findings collected specimens for their research from offshore islands near NSF's Palmer Station on Anvers Island in the Peninsula region.

Surrounded by an ocean, the Antarctic continent is a polar desert where creatures have adapted to life with infrequent access to liquid water. The researchers note that Antarctic midge larvae, for example, "are remarkably tolerant of dehydration, surviving losses of up to 70 percent of their body water."

They also note that, in general, "insects, in particular, are at high risk of dehydration because of their small body size and consequent high surface-area-to-volume ratio."

Among Antarctic insects, the ability to tolerate dehydration is an important evolutionary development, allowing the creatures to successful survive the cold and dry southern winter.

"The loss of water enhances acute freezing tolerance," they write. "In addition, overwintering midge larvae are capable of undergoing another distinct form of dehydration, known as cryoprotective dehydration.

Cryoprotective dehydration is a mechanism in which a gradual decrease in temperature in the presence of environmental ice "creates a vapor pressure gradient that draws water out of the body, thereby depressing the body fluid melting point and allowing larvae to remain unfrozen at subzero temperatures."

The researchers compared the midge's strategy to those of other terrestrial arthropods that cope with prolonged periods when water is lacking, including the Arctic springtailMegaphorura arctica and Folsomia candida, which are more widely distributed across the globe; both species are members of a group of arthropods, which are closely related to insects, known as Collembola.

The differences, they concluded, lie in the way that various genes express themselves.

After a detailed analysis of gene expression in the various species, the researchers concluded that "although B. antarcticaand M. arctica are adapted to similar environments, our analysis indicated very little overlap in expression profiles between these two arthropods."

They add that "these differences in expression patterns may reflect different strategies for combating dehydration; whereasB. antarctica shuts down metabolic activity and waits for favorable conditions to return, F. candida [instead] relies on active water-vapor absorption to restore water balance during prolonged periods of desiccation."

They further add that because of the taxonomic difference between the Antarctic midge and the collembolan species with which gene expression was compared, more work is needed "to better understand the evolutionary physiology of dehydration tolerance in this taxonomic family."

(NSF,march 11,2013)