* Dollar surge resumes; index hits new 13-month high
* Turkish lira extends bounce but many early gains fizzle
* Stronger dollar pressures commodities, copper, gold, oil slide
* Indonesia raises rates for fourth time since May
* World stocks down half percent, EM stocks slump 2 percent (Updates throughout)
By Sujata Rao
LONDON, Aug 15 (Reuters) - The dollar resumed its rise on Wednesday, surging to new 13-month highs and upping pressure on commodities, emerging markets and global stocks, though the Turkish lira managed out to eke out a second day of gains.
Wall Street futures pointed to a sharply lower opening.
The lira, a big focus for markets in recent days, bounced as much as 8 percent as authorities tightened the screws on foreign investors aiming to short the currency But having firmed beyond 6 per dollar, most of its early gains fizzled out. TRY=D3
The rebound follows a 36-percent drop over the past month and fears remain that Turkey is headed for full-blown crisis and debt defaults. Failure to tackle galloping inflation and Ankara's diplomatic tiff with Washington, is also keeping investors wary.
Attention has turned once again to the dollar, which opened Wednesday flat but then strengthened 0.16 percent against a basket of currencies .DXY . It is now up more than 5 percent this year.
"The dominant theme in financial markets at the moment is the strength of the dollar," Aviva (LON:AV) Investors head of multi-asset funds Sunil Krishnan said. "We see scope for that move to continue."
"One of the big challenges to risk appetite in markets is if the dollar moves continue and put pressure on riskier assets such as emerging market bonds and so on," he said.
Krishnan saw the lira bounce as fragile, noting Turkey needed "concrete policy action to improve fundamentals and also some improvement in relations with the United States."
As the dollar rise hit commodities, European stocks fell half a percent. .STOXX
Copper prices hit one-year lows, gold slipped to 18-month lows and Brent crude fell almost $1 per barrel CMCU3 LCOc1 .STOXX . The latest copper slide, with three-month futures down 2.5 percent, came after a Chilean mineworkers' strike was averted.
MSCI's all-country equity benchmark fell half a percent .MIWD00000PUS , though it stayed off one-month lows reached on Monday.
The lira collapse and dollar strength are driving a capital exodus from across emerging markets, sending currencies such as the Argentine peso and Indian rupee to record lows. Emerging equities .MSCIEF fell 2 percent, and are down almost 20 percent from January highs.
There are concerns also about China's slowing economy - reinforced by this week's data on investment and industrial output - and the yuan's weakening to 15-month lows against the dollar. That is also pressuring other Asian markets.
Indonesia, acting after the rupiah fell to three-year lows, raised interest rates for the fourth time since May. backdrop to all this is the escalation in global trade tensions, with Beijing now lodging a complaint to the World Trade Organisation to determine the legality of U.S. tariff and subsidy policies. has also raised tariffs on some U.S. products "in response to the U.S. administration's deliberate attacks on our economy", Vice President Fuat Oktay wrote on Twitter. FXTM's global head of currency strategy, Jameel Ahmad, said the U.S.-Turkey tensions reminded investors that "it is not just the United States and China that stand at the heart of the global trade war concerns".
WALL STREET NERVES
There are signs the negative newsflow is starting to affect Wall Street which has so far drawn support from robust company earnings.
The fears are reflected in the SKEW index - a gauge of the cost of put options on the S&P500 index relative to calls.
A put option confers the right to sell an asset at pre-agreed price, while a call offers right to buy. The SKEW has risen this week to the highest since March. A rise in SKEW indicates higher demand for protection against market falls. SKEWX
S&P500 futures slipped 0.6 percent .ESC1 while futures on the tech-heavy Nasdaq index fell 0.8 percent NQc1 .
Trade and tighter central bank policy were stock market headwinds, according to Aviva's Krishnan, who reckons the issues need to be "better discounted in terms of market pricing. It's something investors need to come to terms with in coming months."
All those concerns have driven investors to embrace more stable assets. Aside from the dollar, that includes German and U.S. government bonds, the Japanese yen and Swiss franc. German and U.S. 10-year yields are down more 10 basis points this month. DE10YT=RR US10YT=RR
The strong dollar's biggest victims are emerging currencies but its rise is also pummelling the euro and sterling.
The single currency slipped a further 0.2 percent to a new 13-month low versus the dollar and also extended losses against the Swiss franc. EUR=EBS EURCHF=
Sterling tumbled to below $1.27 for the first time since June 2017, having lost ground for 11 days in a row, the longest losing streak since 2008 GBP=D3 .
<^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Dollar, U.S. Treasuries benefit from safe haven flows
https://reut.rs/2P84bbH Turkey's ripple effect on global assets, so far
https://reut.rs/2KTqwGI S&P 500 'skew' index
https://reut.rs/2PcpiJZ
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