How do I combine variables from two separate JSON sources?

/* 
To do: 
1. Combine tweet count and Facebook like count.
2. Generate new windows for tweet/facebook share on click or selection of Twitter/FB child list items.
*/

var shares;
var count;

var combinedLikes = shares + count; 
var urlCurrent = 'http://www.google.com';
var twitterCountUrl = 'http://urls.api.twitter.com/1/urls/count.json?url=' + urlCurrent + '&callback=?';

var facebookCountUrl = 'https://graph.facebook.com/fql?q=SELECT%20share_count,%20like_count,%20comment_count,%20total_count,commentsbox_count,%20comments_fbid,%20click_count%20FROM%20link_stat%20WHERE%20url=%27' + urlCurrent + '%27';

function getnumString(num) {
  var numString;

  if (num < 1000) {
    numString = num;
  } else if (num < 10000) {
    numString = num.charAt(0) + ',' + num.substring(1);
  } else if (num < 1000000) {
    numString = (Math.round((num / 1000) * 10) / 10) + "k"
  } else {
    numString = (Math.round((num / 1000000) * 10) / 10) + "M"
  }

  return numString.toString();
}



function twitterCount(data) {
  count = parseFloat(data.count);
  $('.twitter').append('<p class="num">' + getnumString(count) + '</p>');
  return count;

}

function facebookCount(data) {
  shares = parseFloat(data.data[0].like_count);
  $('.facebook').append('<p class="num">' + getnumString(shares) + '</p>');
  return shares;

}



$.getJSON(twitterCountUrl, twitterCount);

$.getJSON(facebookCountUrl, facebookCount);


$('.share').append('<p class="num">' + getnumString(combinedLikes) + '</p>');

console.log(combinedLikes);
console.log(typeof combinedLikes);


$('#social ul').on('mouseover click focusin', function() {
  $('.facebook, .twitter').slideDown("slow");

}).on('mouseleave focusout click', function() {
  $('.facebook, .twitter').hide();
});

$('#social .twitter').on('mouseenter focusin', function() {
  $('#social .twitter').html('<p class="changed">TWEET<br>TWEET<br>TWEET</p>');
}).on('mouseleave focusout', function() {
  $('#social .twitter').html('<p> tweets</p>');
  $('.twitter').append('<p class="num">' + getnumString(count) + '</p>');
});

$('#social .facebook').on('mouseenter focusin', function() {
  $('#social .facebook').html('<p class="changed">POST<BR>POST<BR>POST</p>');
}).on('mouseleave focusout', function() {
  $('#social .facebook').html('<p> likes</p>');
  $('.facebook').append('<p class="num">' + getnumString(shares) + '</p>');
});

console.log(shares);
console.log(count);