var path = "ftp://ftp.nodc.noaa.gov/pub/data.nodc/woa/BARPLANK";

function processData(form) {
  for ( var i = 0; i < form.Details.length; i++ ) {
    if (form.Details[i].checked) {
      break;
    }
  }
  location = form.Details[i].value;
}

function getData(form) {

   for ( var j = 0; j < form.Data.length; j++ ){
          if (form.Data[j].checked){
          break;
          }
   }

          var ref = form.Data[j].value;
              url = path+ref;
          location = url;
}