While oil and gas spending grew only moderately this year, it is expected to increase significantly next year, as energy companies accelerate activity in the U.S., the Middle East, and Latin America.

According to a recent report by Barclays, oil and gas companies will spend $723 billion next year on global exploration and production, up 6.1% from $682 billion this year, based on a recent survey of hundreds of oil and gas companies. Let's take a closer look at the key drivers of this anticipated spending growth.

North American spending
In North America, Barclays forecasts a more than 7% increase in upstream spending next year, up from a 2% increase this year. The projected growth will be driven by an increased focus on drilling, evaluation and completion activity in key U.S. resource plays, such as the Eagle Ford and Bakken. Over the past few years, dozens of major E&Ps have sold off foreign assets to focus on high-growth domestic plays.

For instance, Devon Energy (DVN 0.84%) divested the vast majority of its international assets a few years ago to finance its North American drilling program, where it sees great opportunities in Texas' Permian Basin, the Mississippi-Woodford trend, and -- more recently -- the Eagle Ford, while Apache (APA -1.26%) recently sold a portion of its Egyptian oil and gas assets to focus on its "growth core" assets in the Permian Basin and Oklahoma's Anadarko Basin.

Similarly, ConocoPhillips (COP 0.39%) dumped assets in Kazakhstan, Nigeria, and Algeria, generating $12.4 billion in proceeds since 2012 that will help finance a ramp up in drilling activity across its roughly 2 million acres in the Eagle Ford, Permian Basin, and the Bakken, while Occidental Petroleum (OXY 0.58%) is selling a stake in its Middle East assets to concentrate on the Permian Basin, where it accounts for nearly a fifth of total production.

James West, Barclays' lead oil services and drilling analyst, added that well inventories in the U.S. are at their highest level ever, providing companies with plenty of drilling opportunities next year and in the years to come. Indeed, many of the above-mentioned companies have thousands of undrilled well locations in the Eagle Ford, Bakken, and Permian Basin.

International spending
Outside of North America, Barclays expects E&P spending to grow 6% to a record $524 billion next year, down from a 10% increase this year. Though activity is expected to remain robust in the Middle East, Latin America, and Russia, international E&P spending won't grow as much as it did this year due to reduced spending growth from the integrated oil majors and from Chinese national oil companies.

Under pressure from shareholders, some of the integrated majors have scaled back their capital programs. For instance, Total (TTE 0.52%) recently said that its spending over the next few years will decline from an expected $28-$29 billion this year to a range of $24-$25 billion through 2017, while Chevron (CVX 0.57%) recently announced a 2014 capital budget of $39.8 billion, down $2.2 billion from this year's expected budget of $42 billion.

Shareholder pressure has also led smaller players, like Chesapeake Energy (CHKA.Q), to reduce their spending dramatically. This year, the company expects to spend just $6.9 billion, which is less than half of its 2012 capital budget of $13.4 billion. In line with its strategy of boosting shareholder returns through unlocking value from its existing asset base, more than 80% of this year's capital budget went toward drilling and completion activities, up from an average of 50% over the period 2010-2012.

The bottom line
One of the reasons why North American oil and gas spending only grew by about 2% this year is because of energy producers' relatively conservative forecasts for commodity prices this year. They were expecting West Texas Intermediate (WTI) crude to average just $85 a barrel and U.S. benchmark natural gas to average roughly $3.50 per MMBtu, which led many to curtail gas drilling.

But next year, companies are forecasting higher average prices of $89 per barrel for WTI and $3.66 per MMBtu for U.S. benchmark natural gas for next year, which provides greater incentive to ramp up drilling activity. All told, energy investors can expect an exciting year ahead.